JFK's nephew, Christopher Lawford, 63, may have died of hot yoga after suffering a heart attack.

Christopher Lawford, nephew of John F. Kennedy, died at 63 on Tuesday while doing hot yoga

Hot Yoga may be to blame for the death of John F Kennedy, a 63-year-old nephew, earlier this week.

Christopher Lawford died Tuesday night when he suffered a heart attack in a yoga studio.

His cousin, the former US representative UU Patrick J Kennedy, told the New York Post that the training "must have been too much for him at that time."

The exact cause of Lawford's death has not yet been disclosed by a coroner, but hot yoga studies can reach up to 105 degrees.

He was the son of Patricia Kennedy and Peter Lawford, a Hollywood actor and member of the legendary Rat Pack with Frank Sinatra.

Christopher Lawford, nephew of John F. Kennedy, died at 63 on Tuesday while doing hot yoga

Christopher Lawford, nephew of John F. Kennedy, died at 63 on Tuesday while doing hot yoga

Lawford was in a yoga studio on Tuesday night when he suffered a medical emergency. He is photographed here with JFK and his cousin Maria Shriver in 1962

Lawford was in a yoga studio on Tuesday night when he suffered a medical emergency. He is photographed here with JFK and his cousin Maria Shriver in 1962

Lawford was in a yoga studio on Tuesday night when he suffered a medical emergency. He is photographed here with JFK and his cousin Maria Shriver in 1962

Kerry Kennedy, cousin of Lawford and daughter of Bobby Kennedy, tweeted a tribute to Lawford on Wednesday

Kerry Kennedy, cousin of Lawford and daughter of Bobby Kennedy, tweeted a tribute to Lawford on Wednesday

Kerry Kennedy, cousin of Lawford and daughter of Bobby Kennedy, tweeted a tribute to Lawford on Wednesday

Patricia Kennedy was one of the nine children of the Joseph P Kennedy clan. Sr. She was the younger sister of JFK and one year older than Bobby Kennedy.

Kerry Kennedy, Bobby's daughter, tweeted photos of Lawford on Tuesday and said the family was in mourning for her loss.

Patrick Kennedy, the son of Ted Kennedy, wrote an extensive tribute to Lawford on Twitter and gave credit to his cousin for helping him to achieve sobriety & # 39;

"The recovery community lost a founding father today," Patrick wrote.

"For the world he was an author, actor and activist, but for the recovery community he was a pioneer, a living proof that long-term recovery was possible."

Patrick wrote about how Lawford had been in "long-term recovery" since the mid-1980s and "helped countless others along the way."

"In my own struggle to achieve sobriety, he always encouraged me to stay the course, giving me love and guidance when I needed it most," he added.

Patrick Kennedy, the son of Ted Kennedy, wrote an extensive tribute to Lawford on Twitter and gave credit to his cousin for helping him to achieve sobriety & # 39;

Patrick Kennedy, the son of Ted Kennedy, wrote an extensive tribute to Lawford on Twitter and gave credit to his cousin for helping him to achieve sobriety & # 39;

Patrick Kennedy, the son of Ted Kennedy, wrote an extensive tribute to Lawford on Twitter and gave credit to his cousin for helping him to achieve sobriety & # 39;

Patrick wrote about how Lawford had been in "long-term recovery" since the mid-1980s and "helped countless others along the way."

Patrick wrote about how Lawford had been in "long-term recovery" since the mid-1980s and "helped countless others along the way."

Patrick wrote about how Lawford had been in "long-term recovery" since the mid-1980s and "helped countless others along the way."

March 14, 1996: Patricia Kennedy Lawford (1924 - 2006) (R) w. son, actor Christopher Lawford (L), and his brother, Senator Edward Kennedy (D-Mass.) w. his wife Victoria (2L). (Photo by Dave Allocca / DMI / Photo Collection LIFE / Getty Images)

March 14, 1996: Patricia Kennedy Lawford (1924 - 2006) (R) w. son, actor Christopher Lawford (L), and his brother, Senator Edward Kennedy (D-Mass.) w. his wife Victoria (2L). (Photo by Dave Allocca / DMI / Photo Collection LIFE / Getty Images)

Lawford was the son of Patricia Kennedy (pictured with Lawford and his brother Ted Kennedy in 1996) and Peter Lawford, a Hollywood actor and member of the legendary Rat Pack

"He gave me the strength and inspiration to take that first step, that leap of faith, and join him on the road to recovery in a new life of sobriety that I never thought possible."

Lawford grew up in a star-studded home, learning Marilyn Monroe's Twist, watching Judy Garland play poker and spending time with Rat Pack members, such as Dean Martin and Sinatra.

"They gave me wealth, power and fame when I gave my first breath," Lawford wrote in his 2005 memoir.

Lawford became addicted to heroin and LSD after he moved to the East Coast with Patricia and attended a boarding school in Massachusetts after his parents' divorce.

Here you can see Joseph Kennedy with 17 of his grandchildren (from LR: Christopher Kennedy, Ted Kennedy Jr., Christopher Lawford, Sydney Lawford, Robin Lawford.) Second row LR: Courtney Kennedy, Timmy Shriver, William Smith, Kara Kennedy, Kennedy with Mark Shriver, Victoria Lawford, Mary Kerry Kennedy, Rear LR: Michael Kennedy, Stephen Smith, Joseph P. Kennedy II, Robert Shriver and Maria Shriver)

Lawford was an actor who also spoke openly about his past battles with drug addiction. He is photographed here with Robert Kennedy Jr, the wife of Kennedy Jr. Mary Richardson, and their children

Lawford was an actor who also spoke openly about his past battles with drug addiction. He is photographed here with Robert Kennedy Jr, the wife of Kennedy Jr. Mary Richardson, and their children

Lawford was an actor who also spoke openly about his past battles with drug addiction. He is photographed here with Robert Kennedy Jr, the wife of Kennedy Jr. Mary Richardson, and their children

He later revealed in one of his books that he became addicted at age 14, eventually contracting hepatitis C while struggling with substance abuse for 16 years.

Lawford said he resorted to drugs as a teenager because of his parents' divorce, as well as the murders of his uncles, JFK and Bobby Kennedy.

He decided to go to rehabilitation after his cousin, David Kennedy, died of a drug overdose in 1984.

That same year he married Jeannie Olsson, the first of three wives and with whom he had three children.

Lawford is represented here with Savannah, Matthew and his son David in an undated photo

Lawford is represented here with Savannah, Matthew and his son David in an undated photo

Lawford is represented here with Savannah, Matthew and his son David in an undated photo

Lawford wrote several books, including Symptoms of Withdrawal: A Memoir of Snapshots and Redemption, which became a best-seller of the New York Times, and What Addicts Now.

Lawford wrote several books, including Symptoms of Withdrawal: A Memoir of Snapshots and Redemption, which became a best-seller of the New York Times, and What Addicts Now.

Lawford wrote several books, including Symptoms of Withdrawal: A Memoir of Snapshots and Redemption, which became a best-seller of the New York Times, and What Addicts Now.

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