Use the menu in Google Calendar and deselect the kids’ calendars

There should 100% be something excluding duplication if you are invited to an event with people you sare calendars with. But there isnt.

Ifyou find a solve for this please comment back.

I had a variation of this problem before, I think it involved different work accounts.

I don't know if you would consider this a solution for your case but I seem to remember they're being a Chrome extension that would merge duplicate events into a kind of zebra stripe color when displaying them in your Google calendar, for me this was sufficient

Thanks for the tip of using a family group, that's very convenient and now I won't have to invite my wife to every single event I create. 🫶

I don't think that will help me, exactly, but it's the right idea. Maybe a different calendar widget that lets me show/hide calendars.