Actually, what I did was rescanned my downloads folder, and I guess I left InSim in there. I took it out, and the things cleared up, so, it might've actually been a hack confliction. After that, I could see that it was the foot symbol, and moved the womrat cage so Shae could play with Papi!
I've had that in my game, as well - HOWEVER, I don't have Pets! I'm using a new (CLEAN) install of the base game, Uni, Nightlife, and OFB, with no mods or hacks! This suggests that it's not specifically a Pets problem, but it is nice to know that I'm not alone with my glitch. I'm not sure what causes it either, it seems to be sporadic.