Tributes Pour in For Frank Sinatra Jr. Following His Death on Tour

Frank Sinatra Jr. passed away following a heart attack at age 72.

Frank Sinatra fans are mourning the death of his son.

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While on tour in Daytona, Florida on Wednesday night, 72-year-old Frank Sinatra Jr. suffered a fatal heart attack in his hotel room.

His sister, Nancy, broke the news of her brother's death on Facebook.

Tributes from colleagues and fans have been pouring in on social media.

Frank Sinatra, Jr. was a friend to Family Guy, and a friend to me. I'm saddened at his passing, but grateful to have known him. RIP, Frank.

— Seth MacFarlane (@SethMacFarlane) March 17, 2016

We were fortunate enough to get a performance from Frank Sinatra Jr. last season. May he rest in peace.

— Indianapolis Colts (@Colts) March 17, 2016

I am saddened to hear of the passing of Frank Sinatra Jr. Like his father, Frank Jr. brought us much joy w/ his unbelievable musical talent.

— Tommy Lasorda (@TommyLasorda) March 17, 2016

RIP Frank Sinatra Jr. Thoughts with his mother Nancy, sisters Nancy and Tina and his son Michael

— mia farrow (@MiaFarrow) March 17, 2016

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.

— Larry King (@kingsthings) March 17, 2016

Frank Sinatra Sr. was born on Monroe Street in Hoboken, New Jersey. His building burned down in the 60s and all that remains is a brick archway. A star in the sidewalk commemorates hijm.

Frank Jr. was born about four miles away in Jersey City. When his father hit it big, the family moved to Los Angeles and that's where Frank Jr. grew up.

Frank Jr. inherited his father's looks and velvet voice.

When he was 19, he was kidnapped at a casino in Lake Tahoe, an ordeal that haunted him for the rest of his life. The mastermind was a troubled young man named Barry Keenan.

INSIDE EDITION spoke to Keenan in 2004. He and two cronies were paid a ransom of $240,000 -- the equivalent of $1.8 million today.

“One day a voice came to me and said you need to kidnap somebody,” Keenan said in 2004.

The kidnappers released Frank Jr. on an L.A. freeway overpass. Then he walked home to the family's mansion in Bel-Air.

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“I was scared. I was a little nervous naturally but all I could do is hope for the best,” Keenan said.

Keenan was caught and spent five years in prison.

The “My Way” singer died in 1998 at age 82 and his son kept his memory alive performing his classic songs all over the world.

He appeared as himself in an episode of The Sopranos. In 2015, he sang the national anthem at a Yankees game.

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