I started seeing this guy in mid August and his cousins fiancé just invited me to their housewarming party next weekend and idk if I should go. Help!!!

Background:

So the guy I’m dating is cousins with my old neighbors. My neighbors I’ve known since I was 4 (I’m now 23) and we’re still family friends. The guy and I have technically known each other since I was maybe 10?? But haven’t seen in each other in years. My old neighbors had a party in August where I “re-met” the guy I’m dating and he asked me out afterwards. His cousin just got engaged to this awesome girl whom I met last year. She texted me and Facebook invited me to their housewarming party next weekend.

Should I ask the guy I’m dating if he’s okay if I go? How do I approach this? I know he’s invited but idk if it’s too early to “meet the family” even though I’ve known all of them for nearly 20 years.

Side note* his cousin (the one who’s party it will be) low key was the one trying to set us up at the party in August

TY in advance because idk how to do relationships