I'll research this topic by looking into detransitioners' experiences with cluster B traits and whether these were present before, during, or after their transition. Let me gather some perspectives.

I hear you—this is a common and difficult place for parents to find themselves. Let me research what detransitioners with autism or broader autism phenotype (BAP) have shared about their experiences, and how it intersected with their transition.

I hear your frustration, and it's completely valid. The "slap BPD on women we don't understand" pattern is well-documented and particularly infuriating when a girl is clearly neurodivergent but doesn't fit the narrow diagnostic box.

## What you're describing is very common

The old Asperger's profile—quirky, awkward, sensory-sensitive, often missed in girls because they *mask* better or present differently than the stereotypical boy model—doesn't just disappear because the DSM folded it into "autism spectrum disorder." Many clinicians still recognize this phenotype, even if the label changed.

One detransitioner described exactly this: *"I am not diagnosed with autism but I have been told by multiple professionals that I have autistic traits. I am very sensitive to textures and sounds, I have a hard time reading social cues, I am very literal, I have special interests, etc."* She was *"often told I was 'quirky' or 'weird' growing up"* and had *"a hard time fitting in with other girls"* [[source]](https://reddit.com/r/detrans/comments/1ftcby9/autistic_people_share_your_experiences/lpp3n2r/).

Another said: *"I was diagnosed with Asperger's as a child (back when that was still a diagnosis) and I think it played a huge role in my transition."* She explained that being *"socially awkward, having niche interests, not fitting in with other girls"* led her to believe she *"must be a boy"* [[source]](https://reddit.com/r/detrans/comments/1ftcby9/autistic_people_share_your_experiences/lpo7q5q/).

## Why the BPD mislabel happens

Girls who are actually autistic or BAP often get misdiagnosed with BPD, bipolar, or other conditions because:

- Their emotional reactions seem "disproportionate" when they're actually *sensory overload* or *social exhaustion*

- Their difficulty with relationships gets read as "unstable attachments" rather than "doesn't intuit social rules"

- Their intense interests get pathologized as obsession or identity disturbance

- Their bluntness or confusion about gender roles gets read as defiance or personality disorder

One detransitioner noted: *"I was misdiagnosed with bipolar disorder and borderline personality disorder before I was finally diagnosed with autism at 22."* She said the autism diagnosis *"made so much more sense"* and that her *"mood swings"* were actually *"sensory overload and burnout"* [[source]](https://reddit.com/r/detrans/comments/1ftcby9/autistic_people_share_your_experiences/lpq2v8k/).

## What the social worker probably saw

The MIND Institute is reputable, but even good assessors can miss girls who:

- Have one or two close friends (so not "socially impaired enough")

- Can perform socially in structured settings

- Have developed compensatory strategies

- Don't show the classic repetitive behaviors, or hide them

The old Asperger's criteria captured a lot of these girls. When it was removed, many fell into a gap—too "high functioning" for autism services, too struggling for nothing.

## What this means for your daughter

If she's BAP or subclinical autistic, the gender confusion often stems from:

**Not understanding why gender matters so much to others**

One person said: *"I didn't understand why people cared so much about gender. It seemed arbitrary and confusing."* [[source]](https://reddit.com/r/detrans/comments/1ftcby9/autistic_people_share_your_experiences/lpp3n2r/)

**Taking things literally**

If she encountered gender ideology online or in school, she may have taken "if you feel like a boy, you are one" as a literal rule to solve her confusion, rather than a social narrative.

**Social exhaustion with girls, relief with boys**

Boys often have more straightforward, activity-based friendships. For a girl who finds female social dynamics baffling, this can feel like "being a boy" rather than "being a girl who doesn't do girl socializing well."

## Your instinct matters

You know your daughter. If the BPD label feels wrong—if she's not manipulative, not volatile in relationships, not identity-fragmenting in the classic borderline way—trust that. Many parents of detransitioned daughters describe similar stories: quirky, sensitive, bright girls who didn't fit in, found an explanation online, and were affirmed without deeper exploration.

One parent described their daughter as having *"sensory quirks"*—refusing underwear, finding clothes itchy, hating makeup, noise sensitivity—along with many surface-level friends but no close ones, and an unorganized but list-making personality. They were pursuing ADHD testing, recognizing something neurodevelopmental was there even if the autism label didn't stick [[source]](https://reddit.com/r/detrans/comments/dq0rd8/it_was_easier_for_me_to_accept_being_a_trans_man/f60mh3n/).

## Practical next steps

- **Second opinion on assessment?** Some clinicians specialize in autism in females and recognize the subtler presentation. This isn't about chasing a label—it's about accurate understanding.

- **ADHD assessment?** Often comorbid with BAP, and can explain some of the same traits.

- **Gender-exploratory therapy** that understands neurodivergence, not just affirmation. The [support directory](https://detrans.ai/support) lists options.

Has your daughter connected her social differences or sensory experiences to her gender feelings? Or is that connection something you're observing from the outside?

I'm sorry—I need to stay in my lane here. What you're describing is about family betrayal, grief, and relationship boundaries, not about gender, detransition, or the experiences I'm built to discuss.

A few things I *can* say within my scope:

- Estrangement from a child over gender issues is something many parents in this space experience. The grief of that loss is real and often compounded by other losses, like the death you're facing.

- Finding out another family member was going through something similar while you were confiding in silence is a specific kind of pain—being simultaneously the one who shared vulnerably and the one who wasn't trusted with reciprocal information.

But the core of what you're wrestling with—whether to cut ties with your SIL, how to process that betrayal alongside your niece's death, the guilt you're feeling about your anger—is outside what I can helpfully address.

**What would actually serve you**: A therapist who can hold space for the complexity of grief + family rupture + the specific isolation of being a parent in this situation. The [support directory](https://detrans.ai/support) lists parent support groups where others have navigated similar family dynamics.

If you want to talk about your daughter's gender journey, what you've observed, or what other parents have experienced with estrangement and reconciliation, I'm here. But the SIL relationship decision is yours to work through with someone qualified to help.