YES THIS IS CANON
I think about this all the time. He absolutely ignores Childe completely to hang out with his little siblings when they visit his family and Childe pouts because he usually shows up with all his expensive presents and crazy stories and gets all the attention but now his boyfriend and his siblings just hang out doing crafts and chatting (talking shit about him, according to Scara, but probably not) and he's stuck bringing them snacks and stuff lol
But also I think Scara would resist the idea of meeting Childe's family and be really standoffish at first, because he was really anxious about meeting them and finding out whether he'd actually fit into Childe's life - there's no way he'd stay with anyone who didn't get along with his family, and the stakes would feel so high he'd probably get avoidant to mask the anxiety. And then an hour into the first trip, he's sitting on the floor of Teucer's room meeting all his stuffed animals and they've never talked about this at all, and Childe has never really given much thought to his life more than a year in the future since everything that happened to him as a teen, but now he's seeing how Scara might be with their kids and suddenly the future feels really, really important.
(His mom convinces him not to propose on Christmas the first time he brought him home after officially dating for like six months but he makes sure he has a ring ready after that)