Sisters get nothing in moms will

Pearl

So to start off, I have three sisters and we share a mom. They all share the same dad and our mom is still with my dad. There’s a lot of drama between them and our mom, mostly because they prioritize their dads family just because he has a lot of money, whereas our mom and my dad are in middle class. We only see them once a year, and when we do, they always suddenly say that their dad invited them for dinner or a “family gathering” so they have to leave mid-stay. I’ve never felt like I was treated like their sister and they treat their cousins on their dads side like their siblings instead of me. They thought they were going to get a big inheritance from their dad until recently, so that’s why they always put our mom and me last. So they found out they weren’t getting shit from their dad so now they’re trying to get closer to my mom and I. My mom sees right through this and told me in private that she and my dad are leaving everything to me. I don’t know how I feel about this though. I don’t want them to hate me when that time comes. Even though they’ve never treated us right, I still love them and don’t want this to cause them to resent me. My mom has every right to choose this and I won’t tell her not to because it’s not my choice, but it still just feels wrong. Should I say something to my mom or just deal with it when the time comes?