5 of Days of Our Lives' Most Drop-Your-Jaw Moments!

Marie Horton fell in love with her amnesia-stricken brother and was so traumatized, she left Salem to join a convent. (NBC Photos Archive)

Falling In Love with Your Brother (1967)

In 1967, Tom Horton Jr.’s family thought he was killed in the Korean War. He later returned to Salem, having suffering from amnesia and with a reconstructed face. He believed his name was Dr. Mark Brooks. Mark later fell in love with his lab assistant, Marie Horton, not knowing she was his youngest sister! When Mark’s true identity was revealed, Marie was so upset by the turn of events that she left town and joined a convent.