In polite company I wait my turn, and they wait for me.

With my family, I used to wait my turn, constantly get interrupted and visibly go silent in the hopes that someone noticed (they never did, and I would retreat further inside my head).

Now with my family, I just interrupt. I know they never meant it personally, and so the most normal thing I can do is interrupt, keep the flow going, and let the waterfall of a conversation steer itself by our contributed paddling