I have a 5year old stepson who I adore, we have hi every weekend and through the holidays. We had a baby girl 4 months ago. My partner's family aren't particularly close and we don't see them often. The exception is his sister maybe who we see every now and then. First time I'd spoken to her was when I was pregnant. She sort of took DP ex's side after the split as she wanted to remain close to their son. DPs ex cheated on him that's why they broke up so it's not like she was sticking by the wronged party. She's actually really nice and I'm pleased for my stepson that he's got someone in his life who unlike his mum is bitter and into a bit of parental alienation. She adores him and sees him nearly everyday but rarely comes to ours when he's here to see both of the children. In fact DPs ex has just had a baby and DPs sister is putting pictures on fb of stepson and new baby and captioning it as 'stepson and his baby sister'. I don't have pics of my baby on fb because I didn't want to but it makes me feel a bit crappy when there are pics as if they are her nephew and niece when it's not he niece at all and she rarely sees her niece.
She came over the other night after I emailed pics of the children and she was saying how much DPs ex lies about us and how she knows it's not true but she doesn't say anything. She admitted that his ex only had a baby because we did and that she thinks she is really hung up on my partner and has convinced herself that he pines after her and I somehow control him away from her. It's mad, it's been years! So me and my partner get criticised in front of stepson and nothing gets said. We already knew this but I wish as she knows it's not true and that it upsets my stepson that she'd stop it.
AIBU to A) expect similar attention from her for my daughter as they are just as much related as she is to stepson and
B) to expect that if she knows how outrageous the exs lies are that she says to please stop it...