my younger sibling is sensitive and cries easily

I’m a teen and idk if this is the right sub to post on but i don’t have anyone else to talk about this too ngl. my parents don’t seem to be doing anything about it…

anyway to be straightforward, whenever me and my other family members get upset at something my sibling did, even something minor, he starts crying and obsessively clings to the person he thinks they’re mad at whenever they’re trying to leave. this doesn’t stop until you reassure him multiple times/coddle him into feeling better.

and when I make a joke, like, when the two of us are picking songs on my phone to play, I jokingly said, “oh, so you don’t like the songs I play?”

and he responds with, “no; I like your songs.”

I just nodded because I thought that was the end of that. But then he began repeating ‘I do,’ each one more defensively than last time before breaking into tears.?? I try to calm him down and try to explain to him it was a joke but he just doesn’t listen to what I’m saying and keeps sobbing.

It’s honestly very frustrating and I hate seeing my younger brother cry but idk what to do about it. It usually ends with me becoming frustrated and angry, snapping at my brother to stop crying and Ik that’s not a good thing to do.