In a loud family, the quiet kid isn’t uninterested. Ask them directly. They’ve probably been waiting.

Volume decides who gets heard at a crowded table, not interest. Somebody who needs a second to find the sentence loses their turn every time to whoever starts talking fastest, and after enough of that they stop trying. The silence looks like indifference and is usually a queue nobody ever reaches the front of.

Say their name and ask them something specific, then hold the gap while everyone else waits. One question is usually enough to get a lot back. If you are the quiet one, starting with a few words rather than a whole thought is a way to claim the turn.