Long story.
Parents separated when I was about 8 years old. Now 40. Dad met new wife pretty quickly. They saw me & my sister every other weekend, took us on summer holidays etc. We had a great childhood. My dad & his now wife went on to get married & have 2 children when I was 18+. Since then they don’t give my sister & I christmas presents, sometimes give us a small amount of birthday money. I went on to get married & have children. We see each other quite regularly, birthday meals etc. We get on well, holiday together occasionally. They pay for their own, now fully grown childrens meals drinks AND their partners, whenever we go out, but never ever ours. They always give grandchildren Christmas/ birthday money but not us anymore. We’re far from comfortable financially whereas they most definitely are. My dad received a huge amount of money from my grandparents, it was expected they’d share with us. It wasn’t. AIBU to be peeved we’re being so differently?