On this day in 1977, teenage singer Shaun Cassidy’s recording of “Da Do Ron Ron” hits No. 1. Cassidy, the son of singer Shirley Jones and half-brother of singer/actor David Cassidy, was starring in TV’s The Hardy Boys Mysteries when he released the record. He sang the song on the series in April 1977. He scored two more Top 10 hits off his album Shaun Cassidy: “That’s Rock and Roll” and “Hey Deanie.”