‘The Waltons’: ‘Erin’ Actor Mary McDonough Said This ‘Three’s Company’ Star’s Advice ‘Saved My Life’

The classic family drama The Waltons ran for nine seasons from 1972 to 1981. Based on the book Spencer’s Mountain by Earl Hamner Jr., the series was set in rural Virginia during the years of the Great Depression through World War II.

Actor Mary McDonough portrayed middle sister Erin Walton for the show’s entire run. When this aspiring actor landed a recurring role on the show, he gave McDonough some much-needed wisdom regarding a personal issue she was having.

Mary McDonough and Kami Cotler of 'The Waltons'
Mary McDonough and Kami Cotler of ‘The Waltons’ | CBS Photo Archive

John Ritter portrayed a minister on ‘The Waltons’

Before becoming a household name on Three’s Company, John Ritter played the young Reverend Matthew Fordwick as a recurring character. Hamner recalled casting Ritter in one of his debut roles.

“I’m proud that was one of John’s first roles in Hollywood,” Hamner said of Ritter in an interview with the Archive of American Television. “He played a young minister who was so sanctimonious and so straight-laced and just such an upstanding person that the entire community was outraged when he inadvertently drank some of the recipe which was made by the two old lady bootleggers, and was unable to deliver his first sermon because he was drunk. John took that role and he ran with it.”

Apparently, Ritter showed his comedic talent while on The Waltons, where he often joked around with co-star Richard Thomas (John-Boy).

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“Not only was he a marvelous actor on the show, but sometimes in movie studios, the set seems to get tense,” Hamner shared. “He and Richard would crack everybody up.”

‘The Waltons’ star went through her teen years on the show

McDonough was cast as Erin when she was 11 years old. She felt pressure as the seasons went on to maintain a certain appearance. The stress began to manifest itself physically in The Waltons star.

“Erin, my character, was supposed to be the pretty one,” McDonough said in 2015 on Oprah: Where Are They Now? “So the message to me became this pressure to be perfect, to look perfect, to act perfect. … That took it’s toll on me.When I was 15 I had an ulcer, my hair started to fall out, I had these rashes on my head, and I remember my parents took me to the doctor. And the doctor said, ‘Well, is she under any pressure?’ And my parents said, ‘No, she’s the luckiest girl in the world — Are you kidding me?’”

Hitting her teenage years, McDonough went through the normal body changes that come along with puberty. Yet her physical shifts didn’t seem to be accepted in a positive light by those on set.

“The wardrobe woman looked at me and said, ‘Well, do you think you could fit in the clothes from last season, or have you gained more weight?'” The Waltons alum recalled. “And it hit me just like a knife in my heart. And I wasn’t fat; I was just maturing. And nobody said, ‘Hey, you’re normal. You’re OK.’”

John Ritter’s words of wisdom

McDonough began to practice unhealthy habits in order to keep her weight down and appear thin on camera.

“When they wrote episodes where I was wearing a bathing suit, I would starve myself and I would lose weight for that episode,” she revealed. “Then after that episode was done I would go over to the truck and eat donuts.”

Ritter took notice of McDonough’s insecurities and advised her to do some important introspection. Taking the time to truly listen to McDonough and give her some practical tools, Ritter was able to steer her on a healthier path. The Waltons star began to pass on that wisdom to others throughout her life.

“He said, ‘No, no, I want you to start doing a journal,'” McDonough said. “And that night I started journaling and it saved my life. … what was a horrible process for me to go through became the work I do today.”