Keith Coogan Reveals the Unexpected Tie Between “Don’t Tell Mom the Babysitter’s Dead” and His Famous Grandpa Jackie (Exclusive)

'Don't Tell Mom the Babysitter's Dead' was released on June 7, 1991

NEED TO KNOW

• Keith Coogan played Kenny, the burnout brother who had a change of heart over a monumental summer in Don’t Tell Mom the Babysitter’s Dead
• The 56-year-old tells PEOPLE a different role initially drew him to the film, which he quickly fell in love with
• The film celebrates its 35th anniversary this year, with Coogan remembering some of the fun going on behind the scenes

Keith Coogan had a feeling he wanted to be in Don't Tell Mom the Babysitter's Dead.

Speaking with PEOPLE in celebration of the film's 35th anniversary, the actor, 56, explains how different the project was when it was introduced to him.

"It was called The Real World. I was up for Bryan, the Clown Dog boy," he says of the fast-food delivery driver and love interest of the main character, Sue Ellen "Swell" Crandell.

However, Coogan had his eye on another role in the 1991 film.

"My family had a thing, they were like, 'Never do the same part back to back.' I had just been the nerdy brother in love with the babysitter in Adventures in Babysitting," Coogan explains. "I loved Kenny in the script. I go, 'What's this 15-year-old layabout? He's got this great arc.' And I asked my agent, but my agent said, 'You're too old.' "

Still, Coogan, who was "19 or 20" at the time, didn't let that stop him from vying for the role of Kenny, the skateboarding slacker and stoner of the Crandell family who experiences major growth throughout the film.

"So I prepared a Kenny kit with a cheap wig and a skull vest and ripped jeans and kept it in the car and auditioned for Bryan with Sharon Bialy and Richard Pagano," he remembers. "After doing it, I asked if I could come back in a few minutes and show them something. And they said, 'Sure, Keith, whatever.' And I went to the car, and I changed out into Kenny, and I came back, kicked the door open in character."

"It was a great risk," he admits. "I'm a real straight-laced nerd. I really am a nerd. I'm more Bryan than Kenny, but I loved the arc and the script and the story and couldn't wait to jump in and work with everybody."

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It would be a few days before the young actor found out he landed the part, news that was "totally beyond me."

"They even invested in wigs, hand-laced human and yak hair wigs," he recalls. "And I'm at the Wigs by Ziggy. He's a classic Hollywood wig maker, and he's about to retire. I'm getting the wig fitted, and they are $3,000 a piece, and two wigs, that's $6,000 just in Kenny's hairpieces!"

He continues, "I look up on the wall, and I see a picture of my grandfather, and I go, 'Why do you have a picture of Jackie Coogan up on the wall?' And they go, 'Oh, his PR people said he had to wear a toupee for appearances.' "

Jackie's acting career started as a child in the 1920s, when he played the titular character in movies like Oliver Twist (1922) and Tom Sawyer (1930). He even starred alongside Charlie Chaplin in The Kid (1921). He went on to play Uncle Fester in The Addams Family and made appearances in a variety of iconic TV sitcoms, such as I Dream of Jeannie, The Brady Bunch, The Partridge Family and more.

The legendary actor, who died in March 1984 at age 69, welcomed four children, one of whom is Keith's mother, Leslie Diane Coogan.

Laughing, Keith notes, "So the same hairpiece maker made hairpieces for Uncle Fester and also made Kenny's wig."

Time in hair and makeup also resulted in a special relationship between the young actor and costar Joanna Cassidy, who played Rose Lindsey.

"Joanna Cassidy also wore wigs in the movie. So one of the things would be that we would have an earlier call time than Christina [Applegate]. So me and Joanna would get in and start giggling all morning. You always know Joanna was coming because you'd hear her laugh," he shares.

Of his costar, he praises, "Joanna is so fantastic. She'll be halfway across the world and somebody will go, 'I'm right on top of that, Rose!' And the dishes are perpetually done."

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