I don't know if this bug has been reported, but I've had it for years. What happens is, when your sim comes home and your dog or cat comes to greet you it's out of sync. The cat\dog has it's paws up in the air on it's own( like when a pet puts it's front paws on you) and the sim is bending down patting where the pet is supposed to be.
Edit by crinrict: Added proper tag, adjusted title
