Stressed for my parents

I feel so bad for both my parents. I'm the youngest daughter, I can't exactly do ANYTHING to help them. My brothers broke out in a stupid argument, one's 20, the other 16. 16 yr old one thinks he's all that, and he's complaining about how 20 hr old keeps leaving the bathroom dirty. But me, 14, ALWAYS cleaning the bathroom, I complained sm AND ACTUALLY CLEANED UP AFTER THEM BOTH, yet 16 thinks JUST complaining will get him somewhere?? Both my parents were yelling, and I just saw them so visibly stressed it breaks my heart. My grandad passed away this yr too, (worst day of my life) and he's my mom's dad. My ma has been sad this whole year, we're muslim and so she didn't feel like celebrating eid. And now her birthdays Monday, I wanna do something for her but don't know what. She told me she doesn't wanna do anything because her dad isn't alive anymore. I don't know what to do anymore. My family's falling apart day by day, and my parents pay so much to religious people to get this disastrous family fixed but its not working. I wish my siblings and I weren't born.