In the episode where the Huxtable family is going to Washington DC. Vanessa doesn't want to go because there is a party she wants to go to on the same day. She got home from school and put on her robe. She was acting gloomy. In one scene, she had a folder with paper and she walked down the stairs and left a trail of paper behind her. Well, her dad (Bill Cosby) starts to talk to her. The camera turns to Vanessa and then turns to Bill Cosby. When it turns to Bill Cosby, the papers on the floor aren't there!!! Then, later, Vanessa goes and picks up the paper and walks up the stairs.