My child sim will bug out when doing some tasks

So far I've only noticed it with three things:

• when I tell him to grab a plate of food he'll take it to wherever to sit down and eat, but then he won't actually eat. He first did this on a vacation lot. Coming back from vacation he was fine but started bugging out again.
• if I tell him to play chess he'll sit at the chess table but do nothing. Also happened on the same vacation lot, fixed for a little while at home, but then started back up when I took him to the park.
• I'll tell him to do his homework and he'll bug out but actually complete it. He just won't look like he's doing his homework. It's the same for extra credit.

Resetting him doesn't seem to work, and I'm not sure how he went back to normal for the little bit that he did before he bugged out again. At the moment he's the only child-aged sim in the household so I can't say that other child sims are acting the same. I'm able to cancel his interactions as normal with no issues.