'AITA for losing it at my infertile SIL for trying to be the second mother of my baby?' UPDATED

"AITA for snapping at my SIL?"

I (22f) gave birth to my daughter seven weeks ago, and since that day my SIL (my husband brother’s wife) who is infertile has tried to make herself the second mother of my baby. She showed up at the hospital uninvited and insisted on looking at me breastfeeding my baby, wanted to co-sign the birth certificate.

Visited us everyday after i gave birth and tried to do skin to skin with my baby, tried to push me to pump so she could feed the baby, called my LO “our baby” as in mine and hers.

Very important context to the story: I tend to mostly, if not only, take baby advice from my own mother since from what she is saying my baby acts like me when i was a baby, her advices have helped me a lot. I am neurodivergent and i have been diagnosed very early in life because of my sever sensory issues, that i am pretty sure my baby also has them.

When I was a newborn i would scream my head off whenever my mom would put me in those baby dresses that had tulle, to this day i cannot touch it. It seams that my baby has the same problem, so to keep her comfortable as she is still little i dress her in cotton or soft crocheted dresses, but mostly onesies.

Two days ago it was my mother in law’s birthday and we decided to go and take the baby with us, she spent most of the time in my arms as both me and her have separation anxiety, other than me, my sister in law was the one holding as she would take her out of my arms even though my LO would scream and cry until she was back into my hands.

I told her multiple times that she should stop doing that and she immediately started guilt tripping saying that she wanted to hold a baby since she could never have one of her own. Let’s just say pp has made me very sensitive so i felt bad for her.

It kept going like this until i stood up to use the bathroom, when I came back my baby and my sister in law were gone, to say i was dying inside is an understatement. I kept looking around the house until i heard my baby scream so loudly i thought she was being tortured.

I opened the door to where the sound was coming from and my sister in law taking pictures of my baby, she had changed her in a dress with TULLE, she knows my baby hates tulle. My baby was screaming and kicking her legs very aggressively as if trying to take off the dress.

I lost it. I started screaming that she was a b-word and if god made her infertile it was for a reason as she was putting my innocent baby through pain for her own pleasure. My husband and his mother heard me and came running upstairs, my SIL had started crying while i was changing my baby.

Then i just lost it and started crying while holding my baby, my husband took us home and i had a strong meltdown while he just held me. My mother in law called me and told me that i should apologize for what i said, and i'm actually wondering if i was too harsh.

EDIT: Thank for all the positive and also negative feedback, I will definitely be apologizing for what i said and updating if something else happens. Also she knew about my daughter hate for that specific fabric EVERYONE did.

BTW i am NOT diagnosing my baby, her aversion for tulle is just something that i also have I AM the neurodivergent one. Do not worry i have spoke to her doctor about it and she agrees my daughter does have a strong aversion from tulle

This is what people had to say to OP:

sparksgirl1223 said:

I stopped when you said she tried to co-sign the birth certificate. WHAT? She may need a psychological evaluation, really. Thats not normal.

RiccoPape6 said:

She DID something insane, you SAID something mean. If you decide to apologize, do it for you.

ilyofthevalley2659 said:

You need to cut her off completely. Why isn’t your husband protecting you?

And nolaz said:

You were harsh but your SIL needs mental health treatment. Her wanting to be on your baby’s birth certificate is very distorted thinking. For her own sake, she should not be exposed to you and baby till she has gotten professional help and the therapist thinks she has recovered enough.

Your husband needs to explain all this to MIL. That it is harming SIL to encourage her delusions that she is in a parental role with someone else’s baby. And that her delusions are affecting you and baby negatively so he won’t subject the two of you to SIL either until she has recovered.

There will be no apology now for what you said — and the two of you will not entertain further discussion about it — until SIL is healthier.

Three days later, OP shared this update:

Since the last post I took a screenshot of all the comments i found helpful and showed them to my husband, we stayed all the night awake (half with the baby and the other half talking)

First of all, turns out my MIL had also to do with this. My husband told me than when he saw me go to the bathroom he immediately started waking towards my SIL to get our baby but his mother stopped him using the fact she needed help moving a table as an excuse to keep him occupied.

We believe my SIL and MIL planned this so she could play mommy to my baby and dress her in something she doesn’t even like. Like someone guessed my husband’s brother (sil’s husband) is the golden child. Spoiled rotten.

After that i started having a weird feeling about this situation and later on the day i called his sister who has been low contact with everyone in the family way before i even started dating my now husband. We talked for a while and then i told her what happened. Turns out im not the only one SIL has tried to do this to.

My husband’s sister had two children, the younger one had colic when he was a baby and she wanted to breastfeed so she had to cut a lot of thing from her diet. My SIL decided to give the baby non safe formula secretly (she knew about the baby sickness) which ended up making the baby very sick.

We both believe that my SIL has a problem with listening to what the mother of the baby says, and doing the exact opposite of what is asked of her, acting as if “she knows better."

After that conversation and also the comments from the previous post i decided it was better to just cut contact with that woman and my in laws (not my husband’s sister though), my husband is on the same page as me and we are looking into moving.

My husband was the one who did the talking, he is way better at boundaries and putting his foot down plus it’s his family, explaining the situation to his family, my SIL of course went crazy on us and told me i was taking her niece away from her just because of tulle and that she had more rights to the baby than me, i feel like she doesn’t understand it’s not about the tulle.

My husband just blocked them without even replying. We are hoping the story ends here, and hopefully we’ll move us soon as possible. Thanks again for the support!