i don’t know what to think

i’m 20, my older brother is 24 and my younger brother is 19. me and younger brother are close, friends as well as siblings. my older brother is idk how to put it nicely he’s weird. very socially withdrawn, odd to talk to, cant deal with his emotions well at all, still lives at home doesn’t work basically a recluse. something’s off but we’re filipino and my mum doesn’t like to accept somethings wrong so never had him tested. my younger brother just told me that when he was younger and my older brother was a teenager he offered him £2 to give him a blowjob. i feel sick and repulsed, idk what to think about it. i started gagging and was like “no i need to repress that” and my younger brother was like “yep gonna push that down in the memory bank”. it’s gonna be hard to not think about, it’s so disgusting. any advice on how to deal with this?