Back to the Track, Jack - S1-E20
Character mistake: When the race ends and the kids are cheering, you can hear Denise call Cliff "Bill" instead of "Dad".
Rudy's Walk on the Wild Side - S6-E18
Character mistake: At the beginning, when Vanessa is begging for money from her dad to buy a CD, Cliff says she can clean the garage. But the Huxtables live in a brownstone townhouse and brownstones do not have garages.
Character mistake: Rudy says that the last time some of Anna and Russell's friends visited them was during their 50th anniversary, and she got rich because they gave her money. In the actual episode of the Golden Anniversary however, the only guests at Anna and Russell's dinner party were the immediate family and Elvin.
Character mistake: Elvin has to sit on a stool at the dining room table and remarks that they are all out of chairs. But when Clair and Vanessa go into the kitchen to talk, there is an empty chair sitting by the kitchen table.
Character mistake: When Dabnis and Vanessa first enter, Vanessa can be heard saying. "Hi, Grandpa. Hi, Rudy," when she is greeting Grandpa and Olivia.
Chosen answer: That is the song "Open the Door Richard."