The Sinatra family said in a statement released to The Associated Press
that the singer died of cardiac arrest while on tour in Daytona Beach. He was set to perform at the Peabody Auditorium, but the concert was canceled after he fell ill and was taken to the medical center.
He began performing musically in his early teens and occasionally appeared alongside his sister, "These Boots Are Made for Walkin'" singer Nancy Sinatra
, on a number of TV variety programs.
At 19, Sinatra Jr. was the victim of a kidnapping when he was forcibly taken by three captors from his hotel room at Harrah’s Lake Tahoe. He was released after two days when his father paid the kidnappers' $240,000 ransom demands.
The kidnapping became worldwide news, and it wasn't long before authorities captured and convicted all three men responsible.
Two years after the kidnapping, Sinatra Jr. released his first album, Young Love For Sale, in 1965. He went on to record five other solo albums, most recently 2006’s That Face!
Sinatra is survived by his son, Michael Sinatra, from his relationship with ex-wife Cynthia McMurry, and his sisters Nancy and Tina Sinatra.