Christopher Lawford Once Credited His Sobriety to Cousin David Kennedy’s Fatal Drug Overdose

Before he was an advocate for sobriety and recovery, Christopher Lawford sank into substance and alcohol abuse, starting at age 12.

In fact, Lawford, the nephew of former president John F. Kennedy, who died Tuesday at age 63, was not the only member of the famed political family to battle addiction.

David Kennedy, the son of Robert F. Kennedy and Ethel Skakel and a cousin to whom Lawford was closest, died of a drug overdose in a Palm Beach, Florida, hotel room in 1984.

“David and I were just best buddies. It’s really hard when you lose someone you care about,” Lawford told PEOPLE in 1991 about David, who had been in and out of drug treatment programs multiple times.

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David’s drug problems began early on. He bought heroin for the first time at age 15 with the money he and Christopher got panhandling in New York’s Grand Central Station, according to David’s obituary published by PEOPLE in 1984.

David’s drug issues led to being hospitalized with bacterial endocarditis, a disease frequently associated with drug abuse, in 1979 and multiple arrests for drug possession and drunk driving. In April 1984, he was found dead on the floor of his hotel room. The 28-year-old’s’ autopsy report later revealed cocaine and Demerol in his bloodstream.

Meanwhile, Lawford’s drug issues, including LSD and heroin, continued until the mid-1980s. In 1980, he was arrested in Colorado for impersonating a doctor in order to get prescription medication.

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Though the charges were later dropped when Lawford completed probation, it was David’s death that fueled Lawford’s determination to get clean. In 1986, at age 30, he entered rehab.

In his 2016 book, When Your Partner Has an Addiction: How Compassion Can Transform Your Relationship (And Heal You Both in the Process), Lawford attributed his unresolved trauma to his parent Peter Lawford and Patricia Kennedy’s bitter 1965 divorce and the assassinations of his uncles JFK and Robert Kennedy.

Lawford’s cousin Patrick Kennedy, who is the youngest son of late Senator Ted Kennedy, also struggled to combat substance abuse, specifically OxyContin. He got sober in 2011.

“I used benzodiazepines, alcohol, stimulants, Adderall, cocaine, you name it,” Patrick recalled in 2016.

“It took me leaving my public life to finally get into long-term sobriety. Before, it was stopping and starting, stopping and starting. That’s the case for most people with these illnesses,” Patrick said in 2013 during a joint appearance with Lawford on the Today show.

Lawford’s father Peter also battled addictions.

A member of the famed Rat Pack, Peter drank heavily and entered the Betty Ford Center a year after his close friend Elizabeth Taylor checked into rehab. “Elizabeth going in there really woke up the joint and made a lot of people, like me, realize they had a problem,” he once said.

Peter died on Christmas Eve 1984 of a heart attack after being hospitalized for alcohol-related liver and kidney problems.

According to Christopher’s cousin Patrick, who spoke to the Associated Press, Christopher died of a heart attack in Vancouver, Canada, where he had been living with his girlfriend and working to open a recovery center.