My Three Sons (1960)

Season 2: Episode 7

Mike wants to go skiing on the weekend with his friends but must also keep up his Spanish studies. So he adopts the learn while you sleep method via use of a pre-programmed record player. Steve's room has just been painted so he decides to sleep in Mike's bed. Mysteriously, he wakes up speaking Spanish, and the next night Bub does the same. Before long they are both uttering phrases they couldn't possibly know.