For many of David Cassidy’s millions of devotees, he remains forever frozen in their memories as the feather-haired ’70s teen idol from The Partridge Family. In reality, he would’ve celebrated a milestone birthday on April 12. “The idea that the little boy I came to know and love as my stepson would’ve turned 70 this year is astonishing to me,” Shirley Jones tells Closer. “And I am grateful for all the wonderful times we shared together.”

David was equally fond of Shirley, 86, who married his father, actor Jack Cassidy, and played his mother on The Partridge Family. “She taught me so much about how to deal with fame and success,” he said. “She’s one of the best human beings I’ve ever known.” He also became close with her sons with Jack: Shaun, Patrick and Ryan.

David Cassidy and Shirley Jones Photos
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But David, who died of liver failure at 67 in 2017, didn’t have the kind of idyllic home life that the Partridges portrayed on TV. Jack and his wife, Evelyn Ward, were both traveling actors, and David was raised by his grandparents in West Orange, N.J. “David had to find out from the neighborhood kids that his dad divorced his mom,” Chip Deffaa, who coauthored his memoir C’mon, Get Happy, tells Closer. “That left a scar — who could he trust?”

That wasn’t the only emotional damage Jack inflicted on his son. After David became a superstar, Jack “found it difficult to cope with my fame and success and that he had not achieved a higher level,” David said. “I loved and admired him, but I just couldn’t find a way for him to have it be OK for him.”

David struggled with success as well. “I became so famous, isolated and unhappy, I had to do anything I could to end it,” he said. But after the show left the air, David couldn’t rest. “There were bad investments and he partied too hard,” says Deffaa. Admitted David, “I was one of the wealthiest young male entertainers in the world, but then I had nothing to show for it. By the ’80s, I was broke.”

His romantic life was equally turbulent. David’s first two marriages — to actress Kay Lenz and horse trainer Meryl Tanz — ended in divorce after only a few years each. He had a daughter, Katie, in 1986 with fashion model Sherry Williams, but “I’ve never had a relationship with her,” David said of Katie. “I was her biological father but I didn’t raise her.”

David began to turn things around when he wed Sue Shifrin and had a son, Beau, in 1991. “His birth changed my life,” David said. “As a father, I do everything my dad didn’t do.” Agrees Deffaa, “When Beau started Little League, David not only made sure he went to every game, he also became Beau’s coach. Becoming a good father meant more to him than making money or having a hit.”

David Cassidy, Sue Shifrin Photos
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Sadly, David developed a dependence on alcohol over time, and his addiction caught up to him in his final years, when he was arrested multiple times for DUI. He and Sue divorced shortly before his death, but his fans never stopped loving him. “He gave them so much happiness,” says Deffaa. “I wish he could’ve experienced more of it himself.”

Bruce Fretts, with reporting by Katie Bruno

For more on David, pick up the latest issue of Closer magazine, on newsstands now.