Same here. These are bunnies from the wild rabbit home stump on my home lot. There's four bunnies that my four sims have developed high friendship with and named and all that. Two of them have recently become frozen as described above. Sit in one spot, idle animations. only dialogue option available is 'show dance move'. I've reset the bunnies, I've reset the rabbit home, I've traveled away and back to the lot, restarted the game, moved them around in build-mode, nothing seems to help. They have gardening help enabled, and at least one sim per rabbit has max relationship with them.
Edit: I just shift clicked the rabbit home on the lot and chose 'Call out Particular Rabbit (Debug)' and the two stuck frozen rabbits are not in the list. So somehow they are not a part of that rabbit home's rabbit list anymore. I don't know which came first, if being culled from the list bugged them, or if they first became bugged and then the rabbit home ceased to recognize them anymore, but figured I'd add the info here.