John F. Kennedy's nephew Christopher Lawford dead at 63

The Kennedy family is mourning the loss of Christopher Lawford.

Lawford's rep confirmed the sad news of his death to ET on Wednesday. Aside from being known for his famous family -- Lawford was the son of the late John F. Kennedy's sister, Patricia Kennedy, and actor Peter Lawford -- Lawford had acting roles on multiple hit TV shows including FrasierGeneral Hospital and All My Children. His movie roles included Terminator 3: Rise of the Machines and Thirteen Days, which interestingly enough, featured his famous uncles, John and Robert Kennedy, as characters.

Lawford was 63 years old.  

According to Lawford's cousin, Patrick J. Kennedy, the actor died of a heart attack.

16 PHOTOS
Christopher Lawford
See Gallery
Christopher Lawford
BEVERLY HILLS, CA - SEPTEMBER 09: Author Christopher Kennedy Lawford arrives for the Annual Brent Shapiro Foundation For Alcohol And Drug Prevention Summer Spectacular at a Private Residence on September 9, 2017 in Beverly Hills, California. (Photo by Greg Doherty/Getty Images)
LOS ANGELES, CA - OCTOBER 02: Author Christopher Kennedy Lawford attends the 'Rock To Recovery' bvenefit at The Fonda Theatre on October 2, 2016 in Los Angeles, California. (Photo by Paul Archuleta/Getty Images)
NEW YORK, NY - MAY 14: Christopher Kennedy Lawford, Elizabeth Kabler and Dr. Michael Kraus attend the New York Center for Living Annual Gala at Espace on May 14, 2014 in New York City. (Photo by Cindy Ord/Getty Images)
NEW YORK, NY - MAY 14: Actor/ author Christopher Kennedy Lawford speaks during the New York Center for Living Annual Gala at Espace on May 14, 2014 in New York City. (Photo by Cindy Ord/Getty Images)
NEW YORK, NY - MAY 14: Actor/ author Christopher Kennedy Lawford and Dr. Marianne Chai attend the New York Center for Living Annual Gala at Espace on May 14, 2014 in New York City. (Photo by Cindy Ord/Getty Images)
NEW YORK, NY - MAY 14: Nand Khemka, Christopher Kennedy Lawford, guest and Princess Jeet Nabha Khemka attend the New York Center for Living Annual Gala at Espace on May 14, 2014 in New York City. (Photo by Cindy Ord/Getty Images)
SANTA MONICA, CA - JANUARY 03: Author Christopher Kennedy Lawford (L) and actress Melody Anderson attend a signing for Lawford's book 'Recover to Live: Kick Any Habit, Manage Any Addiction' at Barnes & Noble 3rd Street Promenade on January 3, 2013 in Santa Monica, California. (Photo by David Livingston/Getty Images)
BEVERLY HILLS, CA - OCTOBER 27: Dr. Drew Pinsky, Christopher Kennedy Lawford and Bob Forrest attend Friendly House LA Annual Awards Luncheon Gala at The Beverly Hilton Hotel on October 27, 2012 in Beverly Hills, California. (Photo by Mark Sullivan/WireImage)
BEVERLY HILLS, CA - OCTOBER 24: Christopher Lawford arrives to the Friendly House 20th Annual luncheon held at The Beverly Hilton Hotel on October 24, 2009 in Beverly Hills, California. (Photo by Michael Tran/FilmMagic)
BEVERLY HILLS, CA - OCTOBER 24: Friendly House president of the board Wendy Slavkin and author Christopher Kennedy Lawford arrives at the 20th Annual Friendly House Luncheon at The Beverly Hilton Hotel on October 24, 2009 in Beverly Hills, California. (Photo by Angela Weiss/Getty Images)
Christopher Kennedy Lawford and Lena Antonova during 2007 MusiCares Person Of The Year Honoring Don Henley - Arrivals at Los Angeles Convention Center in Los Angeles, California, United States. (Photo by M. Tran/FilmMagic)
Christopher Kennedy Lawford and Lana Antonova (Photo by L. Cohen/WireImage for The Recording Academy)
LOS ANGELES, CA - FEBRUARY 06: Actor Christopher Kennedy Lawford and Lana Antonova arrive at the 2006 MusiCares Person of the Year honoring James Taylor at the Los Angeles Convention Center on February 6, 2006 in Los Angeles, California. (Photo by Stephen Shugerman/Getty Images)
HOLLYWOOD - NOVEMBER 16: (US TABS AND HOLLYWOOD REPORTER OUT) Actor Christopher Lawford participates in a Q&A session at the Variety Screening Series of 'The World's Fastest Indian' at the Arclight Theaters on November 16, 2005 in Hollywood, California. (Photo by Amanda Edwards/Getty Images)
HOLLYWOOD - NOVEMBER 08: (L-R) Actor Sir Anthony Hopkins, actress Jessica Cauffiel and actor Christopher Lawford arrive at the screening of the film 'World's Fastest Indian' during AFI Fest presented by Audi at the ArcLight Theatre on November 8, 2005 in Hollywood, California. (Photo by Kevin Winter/Getty Images for AFI)
LOS ANGELES - OCTOBER 5: Writer Christopher Kennedy Lawford speaks at a signing of his book, 'Symptoms of Withdrawal: A Memoir of Snapshots and Redemption' at Barnes and Noble on October 5, 2005 in Los Angeles, California. (Photo by Michael Buckner/Getty Images)
HIDE CAPTION
SHOW CAPTION
of
SEE ALL
BACK TO SLIDE

"The recovery community lost a founding father today," he wrote, referring to Lawford's openness about battling drug addiction. "My cousin, Chris Lawford, passed away from a heart attack yesterday evening. To the world he was an author, actor, & activist, but to the recovery community he was a pioneer -- living proof that long-term recovery was possible."

Kerry Kennedy, another one of Lawford's cousins, also tweeted about the family's loss on Wednesday.

"We mourn the loss of my cousin Christopher Lawford, Rest in Peace," Kennedy wrote. "Pictured here with our family at the 2004 Democratic Convention and with his wonderful son, David."

According to TMZ, Lawford had a medical emergency at a yoga studio on Tuesday night and later died. The outlet quotes sources as saying his death appears to be from "natural causes."

Aside from being an actor, Lawford released a New York Times bestselling memoir, Symptoms of Withdrawal: A Memoir of Snapshots and Redemption, in 2005, which detailed both his life as a Kennedy and his battle with drug addiction in the '70s and '80s. In 2009, he released Voices From the Front Lines of Addiction and Recovery, which featured essays from Tom Arnold, Alec Baldwin, Jamie Lee Curtis, Richard Dreyfuss, Anthony Hopkins and more.

In 2015, Lawford candidly talked to Parade magazine about battling addiction.

"I was the product of an addictive perfect storm," he said. "We had an entirely different culture in 1969 when I first used drugs. Experimentation, permissiveness and, frankly, ignorance of what this disease is. Another piece of the storm was severe trauma in adolescence. The fact that any of us in [the Kennedy] family survived what we went through is a miracle. [The trauma] obliterated any safety I thought I had and my ability to have relationships with anybody. That’s what made me an addict."

"Addiction is a brain illness, and it’s not limited to one demographic or another," he continued. "You can be an alcoholic in the White House or in the poor house. [Addiction] runs in both sides of my family."

Lawford is survived by his wife, Mercedes Miller, and his three children from his first marriage to Jeannie Olsson.

55 PHOTOS
Celebrities who died in 2018
See Gallery
Celebrities who died in 2018

Aretha Franklin died at the age of 76 on August 16 following a long battle with cancer. Read more here.

(Photo by Ron Galella, Ltd./WireImage)

Renowned celebrity chef Anthony Bourdain died of an apparent suicide on June 8. Read more here.

(Photo: Reuters)

"Superman" actress Margot Kidder died at the age of 69 in May. Read more here.

(Photo by Gilbert Carrasquillo/FilmMagic)

Nancy Sinatra died at the age of 101 in mid-July. Read more here.

(Photo by: NBC/NBCU Photo Bank via Getty Images)

Designer Kate Spade died on June 5, 2018 by suicide. Read more here.

(Photo: Getty)

DJ Avicii died at 28 on April 20. Read more here.

(Photo by Christopher Polk/Getty Images for MasterCard)

Joe Jackson died at the age of 89 at the end of June. Read more here.

(Photo by Leon Bennett/Getty Images for BET)

"Austin Powers" actor Verne Troyer died at 49 on April 21. Read more here.

(Photo by Barry King/Getty Images)

"Damn Yankees" star and gay icon Tab Hunter died at the age of 86 from cardiac arrest on July 7. Read more here.

(Photo by Silver Screen Collection/Getty Images)

The Cranberries lead singer Dolores O'Riordan died at 46 on January 15. Read more here

(Photo by Frank Hoensch/Redferns)

"The Facts of Life" star Charlotte Rae died at the age of 92 in early August. Read more here.

(Photo by NBC/NBCU Photo Bank via Getty Images)

"Frasier" star John Mahoney died at 77 on February 4. Read more here.

(Photo by Brad Barket/Getty Images)

Former "Glee" actor Mark Salling died at 35 on January 30. Read more here.

(Photo by ANDREAS BRANCH/Patrick McMullan via Getty Images)

Rapper XXXTentacion was shot dead at the age of 20 on June 19. Read more here.

(Photo by Miami Dade County Corrections via Getty Images)

Former child star Jon Paul Steuer (right) died on January 1 at the age of 33. Read more here.

(Photo by Bob D'Amico/ABC via Getty Images)

"Ladies of London" star and model Annabelle Neilson was found dead at the age of 49 in mid-July. Read more here.

(Photo by David M. Benett/Dave Benett/Getty Images for Claridge's)

Comedian Marty Allen died at 95 on February 12. Read more here.

(Photo by Ethan Miller/Getty Images)

Actor Jerry Van Dyke died on January 5 at age 86. Read more here.

(Photo by Mitch Haddad/ABC via Getty Images)

Richard "Old Man" Harrison from "Pawn Stars died on June 25 at the age of 77. Read more here.

(Photo by Denise Truscello/WireImage)

Moody Blues co-founder Ray Thomas died on January 7 at 76. Read more here.

(Photo by Jim Steinfeldt/Michael Ochs Archives/Getty Images)

Motorhead guitarist "Fast" Eddie Clarke died at 67 on January 10. Read more here.

(Photo by Fin Costello/Redferns)

Original Mouseketeer Doreen Tracey died at 74 on January 10. Read more here.

(Photo by Ron Galella/WireImage)

Bobby Zarin (left), husband of former "Real Housewives of New York" star Jill Zarin, died at 71 on January 13. Read more here.

(Photo by Gonzalo Marroquin/Patrick McMullan via Getty Images)

Country singer Lari White died at 52 on January 23. Read more here.

(Photo by Scott Gries/Getty Images)

"Storm Chasers" star Joel Taylor died at the age of 38. Read more here.

https://t.co/nFANu8zcs4

Former NBA star Rasual Butler and former "American Idol" contestant Leah LaBelle died in a car crash on January 30. Read more here.

(Photo by Paul Zimmerman/WireImage)

The Temptations vocalist, Dennis Edwards (center), died at 74 on February 2. Read more here.

(Photo by Paul Redmond/WireImage)

"Home Improvement" actor Mickey Jones died at 76 on February 7. Read more here.

(Photo by ABC Photo Archives/ABC via Getty Images)

Actor Reg E. Cathey died at 59 in February. Read more here.

(Photo by Bruce Glikas/Getty Images)

Former E! reality star Lyric McHenry was found at the age of 26 on August 14. Read more here.

Country singer Daryle Singletary died at 46 in early February. Read more here.

(Photo by Mindy Small/FilmMagic)

TV star Nanette Fabray died at 97 on February 22. Read more here.

(Photo by John Shearer/WireImage)

Bollywood actress Sridevi Kapoor died in late February at 54. Read more here.

(Photo by Amlan Dutta/Hindustan Times via Getty Images)

"MASH" star David Ogden Stiers died on March 3 at 75. Read more here.

(Photo by Tibrina Hobson/FilmMagic)

Rapper Craig Mack died at 46 on March 12. Read more here.

(Photo by Johnny Nunez/WireImage)

Former child star Donna Butterworth died at 62 in March. Read more here.

(Photo by ABC Photo Archives/ABC via Getty Images)

Frank Avruch (aka Bozo The Clown) died at 89 in March. Read more here.

(Photo by John Bohn/The Boston Globe via Getty Images)

"Chicago Fire" actress Dushon Brown died at 49 on March 23. Read more here.

(Photo by Timothy Hiatt/Getty Images)

K-Pop singer Seo Min-woo died on March 25 at 33. Read more here.

Actress Susan Anspach died in April at 75. Read more here.

(Photo by Ron Galella, Ltd./WireImage)

Kids' TV host Chuck McCann died at 83 on April 8. Read more here.

(Photo by gotpap/Bauer-Griffin/GC Images)

"One Flew Over The Kuckoo's Nest" director Milos Forman died at 86 on April 13. Read more here.

(Photo by Ernesto Ruscio/Getty Images)

"Full Metal Jacket" actor R. Lee Ermey died at 74 on April 15. Read more here.

(Photo by Ethan Miller/Getty Images)

"Night Court" actor Harry Anderson died at 65 on April 16. Read more here.

(Photo by Ron Galella, Ltd./WireImage)

Country musician and song-writer Randy Scruggs died at 64 on April 17. Read more here.

(Photo by Ed Rode/FilmMagic)

"Twin Peaks: Fire Walk With Me" actress Pamela Gidley died at 52 in April. Read more here.

(Photo by Ron Galella, Ltd./WireImage)

Dennis Shields, "Real Housewives of New York" star Bethenny Frankel's on-and-off boyfriend, died of an overdose on August 10. Read more here.

(Photo by Alessio Botticelli/GC Images)

"The Goldbergs" actor Jackson Odell died on June 8 at the age of 20. Read more here.

(Photo by Alberto E. Rodriguez/Getty Images)

"Sons of Anarchy" actor Alan O'Neill died at the age of 47 in early June. Read more here.

(Photo by Amy Graves/Wireimage)

Former "America's Got Talent" winner Neal Boyd died at the age of 42 in June. Read more here.

(Photo by Virginia Sherwood/NBC/NBCU Photo Bank via Getty Images)

Jerry Marren, the last living actor who played a munchkin in "The Wizard of Oz," died in June at the age of 98. Read more here.

(Photo by John M. Heller/FilmMagic)

Actor Robert Mandan died at the age of 86 in early June. Read more here.

(Photo by Malcolm Ali/WireImage)

Hugh Dane, who played Hank the security guard on "The Office," died in June at the age of 75. Read more here.

(Photo by Mitch Haddad/NBC/NBCU Photo Bank via Getty Images)

Jerry Maren, the last-living "Wizard of Oz" munchkin, died at the age of 98 in early June. Read more here.

(Photo by John M. Heller/FilmMagic)

Founding member of The Bay City Rollers, Alan Longmuir, died at the age of 70 at the beginning of July after a brief illness. Read more here.

(Photo by Waring Abbott/Getty Images)

HIDE CAPTION
SHOW CAPTION
of
SEE ALL
BACK TO SLIDE

Read Full Story