I don't!

My wife does it for me, lol.

I have a group text with my immediate family so we can coordinate semi-regular get-togethers, and I do the same with my own kids, but that's it.

(There's no way I'd be able to get my parents to learn how use anything more complicated anyhow, and just getting everyone in my own household to use a shared calendar was a whole thing. Simpler is better.)

My wife, however, likes staying informed, if not always in touch, and so dutifully does all the obligatory proud parent posting on facebook. She lets me know if anything important comes up from one of the relatives on there.

Distant family stays distant, which is how I like it, because most of them are pretty right wing anyway and the less I have to engage with their gibberish the better. Otherwise I only visit facebook occasionally to browse a shitposting page for a podcast I listen to. It's better this way.