Ryan O’Neal, the Oscar-nominated Love Story actor who starred in some of the most memorable movies of the 1970s, from What’s Up, Doc? and Paper Moon to Barry Lyndon, died today. He was 82.

His death was announced by son Patrick O’Neal on Instagram. Although a cause was not specified, O’Neal had battled various health issues for decades, from a leukemia diagnosis in 2001 and Stage 4 prostate cancer in 2012.

“So this is the toughest thing I’ve ever had to say but here we go,” wrote Patrick O’Neal, a longtime Los Angeles sportscaster. “My dad passed away peacefully today, with his loving team by his side supporting him and loving him as he would us.”

“This is just so hard for us,” Patrick continues in the lengthy message. “Ryan made such an impact and this will be difficult without him. This is and will be a huge void in our lives.”

Tatum O’Neal, Ryan’s daughter and Oscar-winning actress, said in a statement to People magazine, “I feel great sorrow with my father’s passing. He meant the world to me. I loved him very much and know he loved me too. I’ll miss him forever, and I feel very lucky that we ended on such good terms.”

For many years one of the most sought-after stars of his generation, O’Neal appeared opposite other major talents (Barbra Streisand, Ali MacGraw, daughter Tatum) and worked for some of Hollywood’s greatest directors (Peter Bogdanovich, Richard Attenborough, Stanley Kubrick, Walter Hill).

With fame, though, came notoriety. His high-profile and long-term romance and eventual breakup with Farrah Fawcett prompted untold numbers of headlines, many focused on his infidelity. Substance abuse and addictions would dog him and his family, with daughter Tatum and sons Griffin and Redmond especially hard-hit by the disease. His marriages and relationships — the first marriage to the troubled actress Joanna Moore, the second to actress Leigh Taylor-Young (who spoke out about O’Neal’s “temper and volatility”) and the romance with Fawcett — were tempestuous and often ended in acrimony.

In his IG post today, Patrick O’Neal wrote: “Ryan never bragged. But he has bragging rights in Heaven. Especially when it comes to Farrah. Everyone had the poster, he had the real McCoy. And now they meet again. Farrah and Ryan. He has missed her terribly. What an embrace that must be. Together again.”

While his private life often made for less-than-favorable impressions — in addition to the tumultuous romances, there were frequent disputes and hard feelings with at least some of his children — his onscreen performances were some of the most charming and memorable of the 1970s’ golden age of Hollywood.

Born into a showbiz family on April 20, 1941, in Los Angeles, Patrick Ryan O’Neal was the son of writer Charles “Blackie” O’Neal and actress Patricia O’Callaghan. At first dismissing the family business to become a professional boxer, O’Neal competed in two Golden Gloves championships in Los Angeles in 1956 and 1957 and would go on score a worthy amateur fighting record of 18-4 with 13 knockouts.

O’Neal first came to widespread public attention in the 1960s nighttime soap Peyton Place, starring alongside Mia Farrow, and made an easy transition to the big screen. As the heartbroken beau of MacGraw’s doomed Jenny in the massively popular weeper Love Story (1970) made him an overnight heartthrob and “Love means never having to say you’re sorry” a ubiquitous catchphrase and comedy punchline.

He revealed a genuine talent for slapstick comedy in Bogdanovich’s 1972 comedy What’s Up, Doc?, playing the Cary Grant-like foil caught between Streisand’s zany Judy and the brilliant Madelyn Kahn’s nagging Eunice.

Kahn and O’Neal would reteam in Bogdanovich’s classic 1973 Depression-era comedy Paper Moon, with O’Neal showing yet another side of his talent in a by-turns-funny-and-poignant performance as the grifter father of Tatum’s young-but-wised-up Addie Pray. The film made a star of little Tatum, who became the youngest-ever Oscar winner for her performance. That records still stands.

After newly establishing himself as a film comedy star, O’Neal made an abrupt turn in 1975 with Kubrick’s historical drama Barry Lyndon, a film that drew wildly mixed reactions upon its release. Despite four Oscar wins and seven nominations, the picture largely was maligned for its snail pace and, in a Hollywood era that celebrated grit, its sumptuous 18th century visuals. In the title role, O’Neal was criticized as seeming altogether too modern to play William Makepeace Thackeray’s arriviste rogue. But the decades have been kind to both the film and O’Neal’s performance: Today, Barry Lyndon is generally considered one of Kubrick’s greatest endeavors.

While his post-Lyndon credits didn’t quite extend the run of early ’70s successes — a string of high-profile late-’70s flops included Bogdanovich’s love letter to the silent-movie era Nickelodeon, the Love Story sequel Oliver’s Story and Attenborough’s war epic A Bridge Too Far — there were some bright points. His reteaming with Streisand in the 1979 boxing comedy The Main Event was lambasted by critics but embraced by audiences, becoming one of the year’s biggest hits.

The actor’s box office appeal wouldn’t last long, though. O’Neal’s cinematic failures came fast and steady — from the homophobic 1982 gay-panic buddy comedy Partners (with John Hurt) and 1987’s multiple-Razzie nominee Tough Guys Don’t Dance through 1997’s An Alan Smithee Film: Burn Hollywood Burn, an Arthur Hiller-directed satire that reportedly grossed just $52,850 on a $10 million investment. Critic Roger Ebert named it one of his Most Hated Films.

Television, where O’Neal began his career in a 1960 episode of The Many Loves of Dobie Gillis, would prove more welcoming. He co-starred with Alicia Silverstone in the short-lived 2003 comedy-drama Miss Match, made appearances on Desperate Housewives and 90210 and recurred in 24 episodes of the hit David Boreanaz cop drama Bones over 10 seasons from 2006-17.

In 2011, O’Neal and daughter Tatum embarked on an ill-conceived attempt to reconcile after a 25-year estrangement by co-starring in the reality TV series Ryan and Tatum: The O’Neals, broadcast on Oprah Winfrey’s OWN. The endeavor made for uncomfortable viewing, and the series lasted a brief nine episodes. O’Neal later would tell Access Hollywood: “Did I open up? I tried. Does Tatum like me any better? No.”

A public sign of a reconciliation between father and daughter came last April, when Tatum posted an Instagram message saying, “Happy birthday dad I love you.”

O’Neal’s relationships with sons Griffin and Redmond had their own difficulties. Ryan was arrested in 2007 for an altercation with Griffin, and Redmond was arrested at his father’s Malibu home in 2008 for methamphetamine possession. The elder O’Neal instead pleaded guilty to the charge and entered a drug diversion program but publicly would claim that the drugs belonged to his son.

In a 2012 interview with newspaper columnist Cindy Adams, O’Neal was candid about his family life. “Look, I don’t give myself a break,” he said. “I had four children. Only sportscaster Patrick’s OK. Griffin’s in prison. Redmond, who feels terrible guilt, is in rehab. Tatum, rehab. I had my own problems. Is all this my fault? I guess, yes.”

That same year, sportscaster son Patrick wrote in a Huffpost column, “My name is Patrick O’Neal, and my father is Ryan O’Neal and I’m here to stick up for my old man. I love him. I always have and I always will. Tatum wrote a book. I wish she hadn’t…Griffin has gone on TV talk shows for decades demonizing our father, and has sold countless stories to the tabloids trashing Ryan so that he could profit. To partially quote Michael Corleone from The Godfather, I would tell them, ‘Tate, Griff, you are my older sister and brother and I love you. But don’t ever take sides with anyone against the family again. Ever.'”

Ryan O’Neal’s sons and daughter survive him. His actor brother Kevin O’Neal died in January.