‘I Love Lucy’: Desi Arnaz Jr. Began a Whirlwind Romance With an Older Actor – and Lucille Ball Did All She Could to Stop It

Desi Arnaz Jr, far right, with (from left) Gary Morton, Lucie Arnaz, and Lucille Ball in 1965
Desi Arnaz Jr, far right, with (from left) Gary Morton, Lucie Arnaz, and Lucille Ball in 1965 | Hulton Archive/Getty Images

As a young adult, Desi Arnaz Jr. — son of I Love Lucy stars Lucille Ball and Desi Arnaz — fell in love with and began dating a popular actor.

Until, that is, Ball got involved and made her feelings about the relationship known.

Desi Arnaz Jr. and Patty Duke became romantically involved

Desi Arnaz Jr. 1973
Desi Arnaz Jr. 1973 | Ron Galella/Ron Galella Collection via Getty Images

At age 17, Desi Arnaz Jr. began dating actor Patty Duke. Six years older than Arnaz, Duke at 23 was also romantically linked to actor John Astin and had just divorced Harry Falk Jr., an assistant director on her show, The Patty Duke Show.

During her on again/off again relationship with Arnaz, the star of The Miracle Worker married rock concert promoter Michael Tell. The marriage lasted a few weeks and was later annulled.

Later, Duke was diagnosed with bipolar disorder, which was displayed in her erratic mood swings and impulsive behavior.

By the time Duke, who died in 2016, married her husband of 30 years, Michael Pearce, she had married and divorced three times.

“I didn’t know how to be an adult,” Duke said in a 1999 interview with People. “I had no preparation.”

Duke became pregnant and publicly named Arnaz as the child’s father

Patty Duke, 1970
Patty Duke, 1970 | Silver Screen Collection/Getty Images

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The actor found out she was pregnant just before her marriage to Tell. She wasn’t sure who the father of the baby was.

In the meantime, Duke told the press, who was clearly pregnant, that Desi Arnaz Jr. was the father of her child. She gave birth to Sean Astin, who also became a well-known actor, in 1971. She married John Astin in 1972 after his divorce from Suzanne Hahn was settled.

With the press rabid for details on which of the men Duke had been seeing could have fathered her child, Ball spoke to her son about her concern, as he told Women’s Day in 1991.

“Don’t you see that your actions affect other people?,” Arnaz Jr. quoted his mother as saying at that time. “How could you be so irresponsible? Desi, you have to choose. You can either live here and follow the rules, or you can leave. But if you go, you’re entirely on your own.”

Desi Arnaz Jr. left home at age 16

Desi Arnaz Jr., right, with sister Lucie Arnaz
Desi Arnaz Jr., right, with sister Lucie Arnaz | Ron Galella/Ron Galella Collection via Getty Images

Arnaz explained that he chose to move out on his own at age 16, which saddened him in a way, that he was growing up so quickly.

“Mom kept trying to reach out to me,” he said. “She encouraged me to bring my girlfriends over to the house.”

He clarified that while media outlets liked to pit Duke against his mother, Ball was in reality fond of the actor.

“Although the press made them out to be enemies, Mom actually liked Patty Duke,” he said. “What she didn’t like was the idea of me, at 17, having a relationship with a 23 year-old divorcee.”