If you figured out…

Only with a PM

Might be fun to drop hints to them about eccentric relatives you have in common on a thread they’ve posted on. Like things that relative habitually does during the Thanksgiving dinner.

Just be sure the idiosyncrasies you refer to are not THEIRS!

It shouldn’t be too difficult for them to catch on if Toby is not a pseudonym.

I did notice one personal friend posting on this site. I always say hi.

I noticed someone. But they were a one and done and I know they would have been mortified to have been “caught”.

I guess it might depend on the post. If it was something we discussed and they didn’t accept my answer or was something negative about traveling with me, I would definitely ignore and never acknowledge it. Even though it would bother me.
If it was just a general question I would PM them or even text.

Why not?...

I wouldn’t say anything on the forum, but I would give them a friendly call to say we have travel in common & hear about their upcoming trip. : )

This happened to me! It was my BIL! Instead of posting, he called to ask for more specific advice on where he was going. LOL!

I saw a work colleague on Tinder a few years ago. We knew each other pretty well so I was able to have a laugh about it with her.