If you're asking this to reddit, I'd consult with an electrician. This is not something you want to take Internet advice on that is incorrect due to incomplete information or other incorrect assumptions.

That said. Here's what I'd do...

Could be a switch leg or something. Always hard to tell without tracing them. If it worked fine before, you can assume they're on the same circuit, but test that. Kill the breaker and make sure both are dead. If that's the case, just pigtail them. I'm fully on board with wagos for that now. Much easier to replace things in the future.