Ha! That's what this thread is for.
I mean, only Congress can impeach a president, and I don't think the Republicans are going to impeach Trump anytime soon. So even if an impeachable offense is confirmed (which it hasn't been yet) it's unlikely Congress would do anything about it, unless the Republicans lose a ton of seats in the 2018 elections.
There is, maybe one sentence in the Constitution about what to do if the President is mentally or emotionally unfit to serve, but there's a reason we've never used that part of the Constitution before. It's never good to politicize mental health and while politicians are careless about the words they use around mental health they've always been sensitive to accusations against THEIR mental health. So I doubt anyone would seriously try to use that part to get rid of Trump. There's just no way to do that without it coming back to haunt you later...after all, our understanding of mental health changes all the time and what is a problem for one person isn't a problem for another...It's just a can of worms.