I have a question on apping a character that's canonically close to another of my characters, but who would have a good reason not to interact with each other ingame. The characters I'm talking about are both OCs of mine--Vashti and her father. If you remember from Vashti's app, they're rather close to each other; but at the same time they're used to keeping secrets for their family's protection. I can see him wanting to keep an eye on her, but not wanting to tip anyone off to the fact that they know each other in case one of their natures is exposed.

So basically, I can see: Dad makes post.
Vashti: [private] Dad?
Dad: [private] /explains briefly why they shouldn't interact
Vashti: [private] Oh. Ok, I guess.
/They never interact ingame again. They only do this much to make it less weird to other players why they don't interact.

Is this too much interaction/do you think they couldn't avoid interaction later/etc? Basically, is he even appable by me at this point?

If he isn't appable at this point, I might hang onto him anyway in case I ever get tired of Vashti (which I'm not planning on doing anytime soon). So, second question is: can adults app in as TAs, or is that only for students that recently graduated?