Stay out of,it. Not your circus, not your monkeys.

I always correct people who make BIG mistakes. If I like the person I do it in private.

Asshole. Its perfectly fine to spell it, since we all know what you mean. 2 s's replaced with a - changes nothing in the meaning.

Tell him, publicly. Even post a pic or 2 of Obi-Wan as an old guy.

That one shows up frequently on my feed. Mainly with a comment of people being afraid to share for some odd reason. I responded by asking, "Why would anyone one hesitate to post a photo of Ewan McGregor?" I was ignored.

If he deliberately avoids you, then he won't take hearing from/being corrected by you kindly. I would leave him be. He got himself into the situation. He can get himself out.

1. There is no action, A, that you can take in any situation, S, were some person, P, cannot consider you an asshole.

2. You are under no obligation to spare your uncle the shame of his own ignorance; although your compassion for him is commendable, he will probably just see it as trying to get one over on him by correcting him.