Yes. I've tried everything.
What all have you tried? Do you have other Sims in that household, and if so, are they responding normally? Have you checked to make sure you don't have a corrupted game file (a .bad extension on the file)? Another thing you might try, if you haven't already, is to evict the household and then move them back in. That will often fix glitches. If you use mods in your game, are you certain they're up to date?