Frank Sinatra Jr
Frank Sinatra Jr., pictured Oct. 9, 2010, died of a heart attack Wednesday. He was 72. Getty Images

Frank Sinatra Jr., son of the legendary “My Way” singer, died in a Daytona Beach, Florida, hospital Wednesday, CNN reported. He was 72.

His family said he died from cardiac arrest. At the time of his death, the singer, who had a musical career separate from his famous father, was slated to perform Wednesday.

His sister, Nancy, took to Facebook to share the tragic news. “The Sinatra family mourn the untimely passing of their son, brother, father, uncle, Frank Sinatra, Jr. of cardiac arrest while on tour in Daytona, Florida,” she wrote. “Sleep warm, Frankie.”

The Sinatra family mourn the untimely passing of their son, brother, father, uncle, Frank Sinatra, Jr. of cardiac arrest...

Posted by Nancy Sinatra on Wednesday, 16 March 2016

Celebrities like Tony Bennett and Larry King took Twitter to grieve for the singer. “I am deeply saddened to hear of the passing of Frank Sinatra Jr and send my sympathy to Tina and Nancy and the Sinatra family,” Bennett wrote. “I always admired Frank Sinatra Jr. He was born with a hard name to live up to, but I loved his talent and his ability to be forthright,” King said in a separate post.

Singer Robert Davi also issued a statement via Twitter. “My heart goes out to the Sinatra family. My friend, Frank Sinatra Jr., has passed. Saddened - a great talent,” he wrote. “RIP, Frank.”

In the days after the assassination of President John F. Kennedy, Sinatra, who was 19 at the time, was famously kidnapped Dec. 8, 1963. He was held on $240,000 ransom for four days by former high school classmates Barry Keenan and Joe Amsler.

This is a developing story.

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