EXCLUSIVE: Joan Lunden shares the biggest lesson she's learned from having cancer

Former Good Morning America co-host Joan Lunden opens up on Oprah: Where Are They Now? about her battle with cancer.

In 2014, Lunden announced that she'd been diagnosed with breast cancer, and shared her journey in hopes of inspiring others facing similar troubles.

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In this exclusive clip, the 65-year-old reporter and TV personality says the best lesson she's learned from her battle with cancer is "the healing power of support."

See more photos of Joan Lunden through the years:

For Lunden, a lot of that support comes from her family, and she reveals how she came to the decision to talk to her children about her diagnosis.

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"I didn't want my kids to be scare scared, but we were advised [to] tell the kids," Lunden shared. "Family secrets are dangerous, you can have trust issues later in life, the unknown is much scarier than the known [and] they're going to sense something."

Check out the emotional interview when Oprah: Where Are They Now? airs Feb. 13 at 10 p.m. ET/PT on OWN.

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