During a CNN interview last year, Stephen Colbert and Anderson Cooper had a heartfelt discussion about death and grief that went viral after resonating with so many people. Now, Colbert is reflecting on that conversation during a guest appearance on “Watch What Happens Live” with Andy Cohen.

Shortly after the death of Cooper’s mother, Gloria Vanderbilt, Colbert wrote the newscaster a letter, speaking openly about learning to lean into his faith after losing his father and two brothers in a plane crash when he was 10 years old in 1974.

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“You wrote me a letter after my mom died, and in it, you said, ‘I hope you find peace in your grief,’” Cooper said in their CNN interview. “One of the things I’ve been thinking a lot about is how we don’t really talk about grief and loss. People aren’t comfortable talking about it.”

“I was very grateful to have that conversation with Anderson, ” Colbert tells Cohen, who explains that the reason the interview went viral was because it “resonated with so many people,” and adding that Cooper told him their interview was his “most talked-about moment” of the year. In it, Colbert offers words of hope and encouragement as he reflects on how music from the time of the accident is a trigger for him and how “normal” childhood issues became so minor.

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“I think that because the things he was asking me about are common to all of our experiences, but we generally don’t want to talk about them because there’s something about grief that we feel is contagious,” Colbert says.

“The elephant in the room is that while love lasts forever our relationship or our present physical relationship with those we love most doesn’t,” Colbert continues. “We just don’t want to talk about it to invite that particular anxiety or demon into the room, and so I think the fact that Anderson and I just talked about it frankly and from our hearts might have been unusual but not unique. It’s just that we did it publicly.”

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Watch their CNN interview below.