In the episode where Cliff Huxtable is running a track meet at the Penn Relays (not the one where he is running against Tailwind Turner, the one where he is running with Tailwind and a female Olympic runner is running against him) if you watch for when the camera pans towards Claire Huxtable there is a woman sitting next to Claire who has short hair. This woman is Bill Cosby's wife, Camille Cosby.