<p>Frank Sinatra Jr., the son of iconic performer Frank Sinatra, died Wednesday afternoon.&nbsp;</p><p><a href="http://www.tmz.com/2016/03/16/frank-sinatra-jr-dies-death-heart-attack/" target="_blank">TMZ broke the news</a>, saying Sinatra was in Daytona Beach for a concert when he died of a heart attack. Sinatra&#39;s sister Nancy&nbsp;<a href="https://www.facebook.com/NancySinatra/posts/1080902968599556:0" target="_blank">confirmed the news on her Facebook</a>, adding, &quot;Sleep warm, Frankie.&quot;&nbsp;</p><p>Sinatra followed in his father&#39;s footsteps as a singer and was infamously kidnapped and held for&nbsp;<a href="https://www.fbi.gov/news/stories/2013/december/the-kidnapping-of-frank-sinatra-jr" target="_blank">ransom when he was 19</a>. He worked closely with&nbsp;<a href="http://variety.com/2016/biz/news/frank-sinatra-jr-dead-dies-1201732092/" target="_blank">his father as his musical director</a>. Sinatra was 72.&nbsp;</p><p><i>This video includes images from Getty Images and a clip from&nbsp;</i><i><a href="https://www.youtube.com/watch?v=_Wsefb07Yh0" target="_blank">NBC</a></i><i>.&nbsp;</i></p>
LOS ANGELES (AP) — Frank Sinatra Jr., who carried on his famous father's legacy with his own music career, has died. He was 72.
The Sinatra family said in a statement to The Associated Press that Sinatra died unexpectedly Wednesday of cardiac arrest while on tour in Daytona Beach, Florida.
The statement said the family mourns the untimely passing of their son, brother, father and uncle. No other details were provided.
Kidnapped and held for ransom when he was 19, Sinatra Jr. had already followed his dad into the music business by then. He eventually worked for his father as his musical director and conductor. He performed the National Anthem at a New York Yankees game last year.
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