AIBU to think my sister is resentful since I had a baby?

. I was close friends with my female cousin before she had a child. After she had a child, our relationship changed. My cousin completely changed as a person. She became angry, nasty. She lost hert temper at me all the time. We are not close anymore

It sounds as she feels 'left out'. If you were first call for taxi/going out buddy and you went on holiday together, she must have known things would change.

It's sad that she is saying these things about you and your baby. But it's something she needs to get over. Of course you are allowed to talk about your baby. If she wants to spend more time with your parents, why doesn't she invite just them over for dinner.

I agree with the above posters, confronting her isn't going to change anything. It will only cause more friction. I am sure your parents and your middle sister think she is being unreasonable. Ignore her pouts, and comments and enjoy your new baby, given time, hopefully your sister will come round and become 'fun aunty'

Yanbu in that she's fucked off the equilibrium has changed.
No free lifts no holiday buddy... no liste ing to her stuff all the time... now you want to talk about your stuff too.

AIBU to think she’s quite selfish and to confront her about it
You WBU...
Its pointless and wil bring about zero change.
Grey rock / medium chill/ lots of space are the order of the day.

Congrats on your baby!

Edit:
our mum and dad ‘favouritise’ me because I gave them a grandchild and that isn’t fair.
This is honestly pathetic. Love isnt finite. Are your parents are supposed to pretend their grandchild is just a passing nobody so her nose isnt out of joint??? Bizarre way to think...

She sounds petty and childish and I really don't you can do anything with that.
100% don't both confronting her its a waste of time.

You were there to give her lifts, to go out with her and holiday with her. You’re not at her beck and call now, so no use to her.

She has no interest in your child or her parents and is using the ‘favouritism’ card to excuse her from bothering.

She’ll find someone else to ferry her round, go out with and go on holiday with and won’t care that it isn’t you, just as long as she gets what she needs.

Hmmm, yeah sadly, when someone who has been childfree for some time has a baby, they and their childfree friends (or in your case - sister,) sometimes find their friendship falls off a cliff. I lost 3 or 4 friends when I had my DC, they avoided me like the plague and phased me out! I did make 3 or 4 new friends who I met through mum and baby groups though, so swings and roundabouts.

Some people who don't have children don't like to be around people who have children.

It's not a slight or a critisism, it's just how some people are. Some childfree are fine with people with children, (including people who have children after being childfree for a long time.) Some are not.

Never sure if it's that they find mums and babies boring, or if they're jealous and resentful, or if they just don't think you're a good fit anymore, because your priorities have changed. Whether anyone likes it or not, most mums will see their children as the centre of their universe, and some people can't handle that - or just CBA with it.

Sad that this is a sister who you were close to though @Travellingpantss Give her some space, and time, she will very likely come round, She has to surely?! Your babies are her family! (Your DD is her niece...) Reading between the lines, I think she may be a bit resentful.... She should be thrilled for you, and thrilled to have a new little niece. Her behaviour is odd IMO. (I mean to behave like this towards her own sister, and niece...)

Many things are often left unsaid and I’m guessing there’s a lot your sister feels and hasn’t said. Perhaps she so wanted kids and it couldn’t or didn’t happen for her, perhaps she’s incredibly insecure or has low self esteem. If you were close why don’t you talk to her and try and resolve it.

I think it's ok for her to be disappointed that her relationship with you won't ever be the same. If she chose to not have children it will be because she doesn't like them very much and it's human to be disappointed that she now has to choose between tolerating that and not seeing you any more.

Do you think that perhaps she wanted children and it didn't happen. We gave up on IVF and for years I've said I've never wanted them although I would have given anything to have had a child.

Childless by choice, but what choice, she never met the right guy, he didn't want them, they couldn't? So she has distanced herself...I did with my family.

She's chosen not to have children and you've taken the other road. You just don't have much in common at the moment.