Anson Williams says his friend and costar Erin Moran "always brought light into the room"

Erin Moran‘s close friends are still reeling from the news of her death — including the select few who knew about her quiet battle with Stage 4 cancer.

“It’s hard to wrap your arms around it,” says Moran’s Happy Days costar and longtime friend Anson Williams. “She was having treatment for throat cancer, so I was contacting her husband and her and she seemed to be fighting it, really doing well. I was just shocked when I got the call she had passed. I had no idea it was that bad.”

Williams was among a close-knit group of people who knew about the 56-year-old actress’s condition, for which she was receiving radiation and chemo treatments.

“She kept very quiet,” he says. “We all kept quiet too, out of respect for Erin. She couldn’t speak, but her texts were very [positive].”

Credit: Gregg DeGuire/FilmMagic

The actor and TV director, who played Potsie Weber on Happy Days, met Moran began before anyone else on the show and suggested she come in to read for the role of Joanie Cunningham.

“A lot of people don’t know this but after the first Happy Days pilot which didn’t sell, I went back to playing the concerned boyfriend parts and I was working with Kay Lenz on a Hallmark Hall of Fame special around 1973,” he recalls. “Erin Moran played her younger sister. She was so adorable and so good, when they called for the second pilot of Happy Days, they were looking for a different Joanie and I recommended Erin. They brought her in and she got the part.”

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Williams, 67, hopes people remember Moran for the smiling, bright light that she was and played on TV.

“Erin always brought light into a room,” says Williams. “She always gave before she took, she was a very kind, generous person, but going through her own demons. Most of the time when I’d see Erin it would be an event, something kind of special, it would be a couple of days and quality time.”

The actor has high praise for Moran’s second husband, Steve Fleischmann. “She found a good guy in Steve, who really really loves her and really really is there for her,” he says. “They’ve gone through their struggles and came out on top.”

He adds: “Even though she’s gone, she will always be on that TV making someone smile. She does leave a legacy of good feelings and light for anyone that watches her.”