Kelly Clarkson is Carrie Underwood's biggest cheerleader.

During her recent appearance at the 2018 iHeartRadio Music Festival this past Saturday (September 22), the "Stronger" singer nearly reduced to tears remarking on how her fellow American Idol alum's pregnancy journey sparked a meaningful conversation.

"Carrie's killing it, and she's pregnant! What?! I hated singing pregnant," the Grammy winner told Entertainment Online of the country superstar, who recently announced she and her husband Mike Fisher were expecting their second child in August.

While the moment was surely celebratory, Underwood also admitted her road to maternity had been devastated by heartbreak after suffering three miscarriages. The revelation inspired Clarkson to reach out and uplift the "Cry Pretty" artist, as she, too, has had dear ones suffer similar losses.

"I didn't know a lot of the situations that were happening behind the scenes," Clarkson added. "I have a lot of friends who have gone through that several times as well."

She continued: "It's a really cool thing [she did]. I was emailing her, because I was like, 'It's so important that you talk about it.' I know you don't have to, because it's a hard thing to do, but it makes women who feel inferior, or feel like something's wrong with them, it makes them feel comfortable, and [know] that people go through it."

Underwood and Fisher welcomed their first child, a son born Isaiah, in February 2015. The sex of the couple's second baby has yet been revealed.

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