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The actress, 39, said that Kelly, 53, "saved my life" by giving her "permission to just go," as they caught up on Monday's episode of Burton's Drama Queens podcast, along with co-hosts and former costars Sophia Bush and Bethany Joy Lenz.
Burton tearfully recounted the last time she saw Kelly, when she left the show after season 6 in 2009, along with her romantic lead (and Kelly's onscreen son) Chad Michael Murray. Although she wanted to leave the show, Burton said she received a lot of pushback before she sat down with Kelly.
"I was like, 'I don't know what to do,' and you said, 'Run,'" Burton recalled. "You started it off with, like, a joke, and I was like, 'Yeah?' You said to me, 'There's so many chapters in life and this is just one. This is just one.'"
"I so valued your opinion of me and of our business and the way you prioritized your family over work, and that's what I wanted — what you had is what I wanted," she added. "You didn't have to say anything because you lived it and we could just, like, see it…I have wanted to thank you for that, honestly, since I was 26 years old."
"It's like, 'Oh, my God. You don't know that you saved my life.' I don't know what would have happened to me if I stayed," Burton later said. "I met my husband. My son exists because Moira Kelly told me to run. And so I did. I just think about how different my life would be if she wasn't that one person to give me permission to just go."
Burton is one of several from the show's cast and crew who have opened up over the years about inappropriate behavior they say they experienced while filming the hit series, most notably allegations against show creator Mark Schwahn. (Schwahn has never responded to any questions about the allegations.)
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Kelly said on Monday's podcast that she "would have made my presence stronger" if she knew what the other women on the show were allegedly going through. "I felt like, you know, being somewhat of a veteran, you were all so very young coming into this situation, there's a part of me that feels like I let you all down," she said.
"If I had been more present, I would have been more aware maybe of what was going on, I surely would have said something," Kelly added. "I surely would have done something, and so, if I could go back and do anything different, I would make my presence so solid on that show and I would have made myself so available to all of you."