Triangulation: How Narcissistic Parents Use You Against Each Other

NARCISSISTIC ABUSE & BOUNDARIES • April 9, 2026

The Message She Wasn’t Supposed to Tell You

It’s a little past four on a Sunday, the light in the kitchen already going amber, and Rosalind is standing at her mother’s counter holding a mug of tea she hasn’t touched. Her sister is across the room, arms crossed, and the air between them has the particular density of two people who used to be close and no longer know how to be in the same room without flinching. Their mother moves between them like she’s setting a table, refilling a glass here, straightening a chair there, watching.

Then their mother says it, casual, almost offhand, the way she always delivers the sentences that do the most damage. “Your sister thinks you’ve gotten selfish since the promotion.” Rosalind’s stomach drops. She looks at her sister, who won’t meet her eyes. Three weeks earlier, on the phone, her sister had heard something different: that Rosalind had called her irresponsible with money. Neither conversation happened. Not one word of either. But by the time the two of them compare notes, if they ever do, the damage has already done its work.

In my work with driven women over the past fifteen years, particularly those navigating estrangement or near-estrangement from a sibling, I’ve noticed a pattern so consistent I now ask about it directly in a first session: who was the only channel of information between you and your sibling growing up. Almost always, the answer is the same parent who is, not coincidentally, still the only channel today. This is triangulation, and it is one of the most underrecognized forms of relational damage inside narcissistic family systems.

Rosalind didn’t have a name for what was happening for almost four years. “My mother was the only line between me and my sister for most of my adult life,” she told me, months into our work together. “Everything she told me about my sister, and everything she told my sister about me, had been filtered. Shaded. Sometimes invented outright. We were estranged for three years over conversations that never happened.” Understanding that she and her sister had both been played, she said, was one of the most clarifying and devastating realizations of her life. Of course it was. Nobody prepares you to discover that the story of your own family has been ghostwritten.

What Is Triangulation?

Triangulation, in its most basic form, isn’t unique to narcissistic families. Every family triangulates sometimes. A third person gets pulled into a disagreement to diffuse it, or a parent mediates a sibling squabble so it doesn’t escalate. In healthy systems, these triangles form and dissolve without lasting harm. What makes narcissistic family triangulation different is not the shape of the pattern. It’s the function it serves and how long it’s allowed to run.

Rather than supporting the siblings toward direct communication, the narcissistic parent uses triangulation as an ongoing control mechanism. They sit at the center of every conversation, playing one child’s words against the other’s, managing loyalty the way a bank manages currency. The siblings become unwitting participants in a game whose rules keep shifting, and the prize is always the same: the parent’s approval. Here’s the part that breaks my heart every time I see it in session. Both siblings are usually acting in good faith. They’re responding to information they had no reason to question, because it came from their mother or their father, the person who was supposed to be the most trustworthy source in the room.

Think about what it would mean to build a relationship with your sister when every scrap of information you have about her inner life arrived through your mother first. Every resentment, every worry, every scrap of praise, shaped on its way to you by whatever served your mother’s narrative that week. You cannot build something real on information that has been edited by design. This is part of why the betrayal trauma framework is so useful here. It explains why manipulation by a trusted parent lands so much harder than manipulation by a stranger would. The harm arrives through the exact channel that was supposed to protect you from harm in the first place.

I think about that line often in sessions about family triangulation, because it names something clients struggle to articulate. The lies weren’t really about the siblings at all. They were about making one parent’s life simpler. Simpler to manage two children’s loyalty than to sit with two children’s honest, sometimes conflicting feelings about her. Simpler to be the single source of truth than to risk what might happen if the children compared notes and found the story didn’t hold together.

The Psychology of Triangulation in Narcissistic Family Systems

Triangulation as a clinical concept comes out of family systems theory, and Murray Bowen was the one who gave it its name and its structure. Bowen observed that a two-person relationship under stress will almost always recruit a third party rather than resolve the tension directly, and he considered the triangle, not the individual and not even the pair, to be the smallest stable unit in an emotional system. That third-party pull can be temporary and mostly harmless. It becomes dysfunctional when it hardens into the family’s default operating structure, which is exactly what happens in narcissistic households.

Salvador Minuchin, MD, the psychiatrist who founded structural family therapy, extended this work by focusing on cross-generational coalitions: alliances that cross generational lines, pitting a child against a parent or one sibling against another. Minuchin’s core observation was that these coalitions destabilize the family’s boundaries and create dysfunction that outlives any single conflict. In narcissistic families, the cross-generational coalition usually takes a specific and recognizable shape, with the narcissistic parent aligning openly with one child against the other. That’s the golden child and scapegoat dynamic in its most stripped-down form, and it’s often the engine that makes triangulation so durable across decades.

Here’s where I want to translate the clinical language into something you can feel in your own body. Two recent studies looked at the raw numbers behind these family dynamics, and while the statistics themselves are dense, what they point to is simple. One study found that the connection between a parent’s narcissistic traits and how that parent overvalues one child produces a small but statistically significant effect on that child’s own narcissistic traits later in life. Another found that a mother’s narcissistic traits explained roughly 16 percent of the variance in her adult daughters’ emotional balance. Neither number is enormous on its own. Together, they describe something I see constantly in my office: family patterns compound quietly, generation after generation, without anyone ever deciding to build the pattern on purpose.

What I want you to take from the research, more than the numbers themselves, is this. Not every family with a difficult parent produces triangulation this severe. Some families brush up against these dynamics without the system ever calcifying into the control structure I’m describing. But when triangulation does calcify, it rarely stays contained to one relationship. It moves through the whole sibling group, and it moves through generations, unless someone names it out loud.

How Triangulation Shows Up in Adult Sibling Relationships

Sibling relationships tend to absorb the worst of triangulation’s damage. The pattern is subtle at first and then suddenly not subtle at all: tension and low-grade mistrust simmer under the surface, shaped entirely by narratives your parent controls. You find yourself defending choices nobody actually attacked. You second-guess your sibling’s intentions before you’ve even spoken to them that week. Sometimes you catch yourself wondering, did that really happen, or is this just the story I was handed.

Rosalind described watching her relationship with her sister erode over roughly a decade, in the kind of slow motion that makes it almost impossible to pinpoint when things actually broke. “Every time I went home, I came back with some new report about how my sister had been talking about me,” she said. “And every time she went home, she came back with a new report about me. We stopped trusting each other completely, and I didn’t figure out until I was in my forties that neither of us had ever actually said any of it.” The estrangement, once she traced it back, had been built entirely out of fabrications passed through the same set of hands, serving the same single function: keeping both daughters competing for approval instead of forming the kind of alliance that might have let them see the pattern clearly.

driven women are often especially vulnerable to triangulation showing up again in adult professional life, and this is a pattern I now watch for directly with executive clients. The same structure plays out in workplaces where a manager sits as the central node of information, shaping what each team member believes about their colleagues, quietly rewarding competition over collaboration. If you’ve ever walked into a job and felt an eerie familiarity, a sense that the office runs on the same emotional logic as your childhood home, that’s not a coincidence. The patterns transfer almost exactly, because the underlying mechanism, control through information scarcity, doesn’t care whether the room is a kitchen or a conference room.

Lecciso and colleagues (2025), publishing in PLOS One, examined the determinants that shape adult sibling relationships and found that the quality of parental relationships during childhood, along with how directly siblings were allowed to communicate with each other, predicted adult sibling closeness more reliably than almost any other factor studied (PMID: 40267927). That finding lines up precisely with what I see clinically. It isn’t that triangulated siblings don’t love each other. It’s that they were never given the uninterrupted access to each other that closeness actually requires.

Triangulation and Flying Monkeys: When Other Family Members Become Instruments

One of the most painful extensions of triangulation is watching it recruit people who love you. Aunts, uncles, cousins, even the other parent, get pulled in to deliver messages, apply pressure, or reinforce the narcissistic parent’s version of events. Most of these relatives are acting in complete good faith. They genuinely believe what they’ve been told. That’s precisely what makes the situation so much more complicated and so much more painful than if it were only the parent doing the harm. You’re being hurt not only by the person orchestrating it, but by people who care about you and have no idea they’re being used as an instrument.

Rosalind experienced this through her grandmother, who called every week with what sounded like ordinary check-ins but were, functionally, delivery mechanisms for her mother’s narrative. “My grandmother wasn’t a bad person,” Rosalind told me. “She just believed my mother’s version of everything completely, because my mother had been managing that relationship for years before I was even in the picture. My grandmother was carrying a message she didn’t know she was carrying.” Learning to separate someone’s love for you from the harm they’re unknowingly participating in is some of the hardest, most nuanced work in recovering from a triangulated family system. It is not a betrayal to still love your grandmother. It’s also not naive to stop taking her check-ins at face value.

Understanding the flying monkey pattern also explains something clients ask me about constantly: why do extended family members so often side with the narcissistic parent in family conflicts. It’s rarely conscious collusion. More often, the parent has spent years managing that relative’s perception, and the relative is simply responding to information they’ve never had reason to question. That doesn’t make the behavior harmless. But it does make it comprehensible, and comprehensible is a useful place to stand when you’re trying to navigate the inevitable politics of your own healing. If your family has drawn on flying monkeys to enforce its version of events, this pattern is worth understanding fully before you decide how to respond to any one relative, and it often overlaps with the dynamics described in how narcissistic mothers specifically manage family perception.

Both/And: You Can Recognize Triangulation and Still Love Your Sibling

Here’s the truth I want you to walk away from this post holding. Recognizing triangulation in your family doesn’t require you to stop loving your sibling, and it doesn’t require you to recast them as a co-conspirator in your own harm. In nearly every case I’ve worked with, your sibling was inside the same system you were. They were also being manipulated, also receiving distorted information, also operating from a position of incomplete knowledge about what was actually happening to the relationship between the two of you.

You can grieve everything the triangulation cost you and still want to repair what’s left. You can be furious about years lost to estrangement and still recognize your sibling wasn’t the one who architected it. You can name exactly what your parent did, in precise language, and still hold love for everyone caught in the structure. None of these truths cancel each other out. The both/and framing matters here specifically because triangulation was designed to make you believe you had to choose. Loyalty to the parent, or loyalty to the sibling. That forced choice was never a natural feature of the relationship. It was manufactured, and naming it as manufactured is often the first real crack in the whole system.

Celeste, a physician in her mid-forties, came to this both/and slowly, and not without resistance. For years she’d told herself a version of the story where her brother had simply chosen their mother over her, full stop, no complexity required. “I built an entire identity around being the one who got left,” she told me. “It was clean. It was simple. And it let me avoid ever having to feel how confusing it actually was.” What shifted for Celeste wasn’t a single dramatic conversation. It was a slow accumulation of small evidence, an old email her brother had forwarded her by accident, a comment from a cousin that didn’t match the story she’d been told, until she could no longer hold the simple version without contradicting what she now knew to be true.

“I think we were both being managed by the same person,” Celeste eventually said to her brother, not to relitigate the past or compare wounds exhaustively, but simply to open a door. “I’d like to know you without her standing in the middle of it.” That conversation, she told me, was one of the most healing of her adult life, not because it resolved everything between them, but because it allowed something unmediated and unfiltered to begin, finally, on its own terms. She still doesn’t fully trust her brother’s version of certain events from their childhood. She’s decided that doesn’t have to be resolved before they can have a relationship now.

The Systemic Lens: Why Triangulation Is So Effective at Keeping Children Divided

The pattern I’ve just described isn’t a personal failing in your family specifically. It’s patterned, and the pattern has a structural origin that runs deeper than any one parent’s individual psychology. Triangulation is so effective because it exploits something entirely human: our deep need for a trusted source of information about the people we love most. In healthy family systems, parents provide exactly that trusted narration, helping children understand each other, modeling direct communication, reinforcing the sibling bond as something valuable in its own right. When a parent weaponizes that same trusted position instead, the damage runs deep precisely because it targets the mechanism children rely on to make sense of their closest relationships.

The structural force compounding this is the family system’s built-in resistance to being named. Naming triangulation, and especially naming the parent as its source, threatens the family’s entire equilibrium and threatens the parent’s central position within it. That threat creates real pressure on adult children to stay quiet, to attribute sibling conflict to the siblings themselves rather than to the parent who orchestrated it, and to keep operating inside the frame the parent originally built.

Cultural scripts make this worse. “You don’t air dirty laundry.” “Family comes first.” “She’s still your mother.” These phrases do real cultural work, and the work they do is protecting the narcissistic parent’s position, whether or not that’s their conscious intent. Peter and colleagues (2026), publishing in Child Abuse and Neglect, traced how childhood emotional abuse and neglect erode a person’s baseline capacity for interpersonal trust and emotion regulation well into adulthood, a mechanism that helps explain why naming a family pattern out loud can feel almost physically dangerous even decades later (PMID: 42061095). Separately, Park and colleagues (2026), writing in the Journal of Clinical Psychology, mapped how early life stress and stress that continues into early adulthood tend to compound rather than resolve on their own, which tracks with what I see in family systems where triangulation goes unaddressed for twenty or thirty years (PMID: 42400332).

You are not broken for having taken this long to see it. The system was built, deliberately or not, to keep you from seeing it. What I’ve come to think of as the family’s silence tax is the accumulated cost of everyone agreeing not to name what everyone privately suspects. Here’s how that tax shows up on an ordinary Tuesday. It’s the flinch you feel opening a text from your mother before you’ve even read it. It’s the specific hesitation before you call your sibling, the calculation of what she might have already been told about you. It’s the holiday dinner you attend fully armored, tracking who said what to whom, because some part of you learned decades ago that information in this family is never neutral. This same erosion of trust is a hallmark of childhood emotional neglect, where a child learns early that their own perception of events cannot be fully trusted.

Breaking Free of the Triangle

Breaking free of triangulation starts with a real commitment to direct communication. That means bypassing the parent as the information intermediary and building a genuinely direct channel with your sibling, one that doesn’t route through anyone else. This sounds simple and is often brutally difficult, especially if the sibling relationship has already absorbed years of distorted information and the mistrust that follows it. It requires both people to be willing to question the story they were handed, and to hold open the possibility that their whole picture of the other person was shaped by someone with their own agenda.

In therapy, this work usually involves naming the structure itself, out loud, in specific language. That means developing the capacity to recognize triangulation in real time, to notice when information is arriving through an intermediary in a way that serves the intermediary’s needs rather than your own, and to choose direct contact over the triangulated channel even when the triangulated channel feels more familiar. This isn’t a one-time conversation you have and then move past. The narcissistic parent will often try to reinsert themselves into the direct channel once it’s been established, because the direct channel is precisely what the whole structure was built to prevent. Maintaining that direct relationship in the face of the parent’s attempts to reinsert requires steady, ongoing effort, not a single breakthrough moment.

What becomes possible once the triangle actually dissolves is real, and it’s worth naming plainly. Rosalind describes her relationship with her sister now, nearly two years after that first direct phone call, as the most honest relationship she has left in her family. They don’t talk every week. When they do talk, the conversation is real: their actual experiences, their actual feelings, their actual relationship with each other, rather than the version their mother spent decades building for them. Rosalind still keeps the mug from that Sunday afternoon at her mother’s counter, the one she never drank from. It sits on a shelf now, not as a wound she reopens, but as a small marker of the moment she started asking different questions. Her sister called last month, unprompted, just to talk. That’s new. It’s not everything. It’s real.

Of course this work is slow. Of course it asks you to tolerate uncertainty about a story you’ve told yourself for years, sometimes decades. Recovery from this kind of relational pattern is possible, and you don’t have to navigate it alone. It requires patience with yourself, patience with a sibling who may not be ready to see the pattern as clearly as you do, and a willingness to build something honest even when honest feels riskier than the old, familiar distortion. Warmly, Annie.

Related Reading

Bowen, Murray. Family Therapy in Clinical Practice. Jason Aronson, 1978.

Minuchin, Salvador. Families and Family Therapy. Harvard University Press, 1974.

Herman, Judith. Trauma and Recovery: The Aftermath of Violence, From Domestic Abuse to Political Terror. Basic Books, 1992.

Forward, Susan. Toxic Parents: Overcoming Their Hurtful Legacy and Reclaiming Your Life. Bantam Books, 1989.

Medical Disclaimer