AITA for telling my mom to stop using my dead sister's name as if she was still here after 30 years since her passing?

My sister passed away when she was only 5. Cause of death was a drowning. She was bathing with me and I was 9 at the time. I'm only starting with the backstory.<br><br>I've always been a good son, never been in trouble.<br><br>My parents are loud people. They love to talk about their dead daughter. And they love to talk to her as if she is still alive. They buy her toys, clothes, shoes. I try to avoid it and not talk about it or tell them to stop. But I think this needs to stop, but my girlfriend says I'm an asshole if I tell my parents to stop.<br><br>My mom for example shouts "let me take care of you two" or "here are some new clothes for my two babies" (the toys and clothes go straight into the garbage)<br><br>I don't talk about my sister.<br><br>It's been 30 years but nothing changed.<br><br>I asked my mom to stop and she told my dad on me. He came and shouted at me to get my own house and that I have no right to talk to my mom like that. Since I live with them. I'm 39 now but the house I inherited from my grandfather is currently being used by one of my younger cousins (with my parent's approval) so I have no other option but to live with my parents.<br><br>Now they are making a huge fuzz about it so my brother got involved after his wife told him what happened and he asked my parents to stop. Then my mom got upset because none of her sons care about their baby sister. And that we're all assholes.<br><br>My girlfriend got mad at me when I told her what happened. She says these are my parents and I shouldn't tell them what to do.<br><br>I'm so confused. Aita?