Kelly Clarkson raved to Entertainment Tonight about her friend and fellow American Idol champ Carrie Underwood's candid discussions about miscarriage

Kelly Clarkson couldn’t be prouder of her friend and fellow American Idol champ Carrie Underwood.

Speaking to Entertainment Tonight Saturday at the 2018 iHeartRadio Music Festival in Las Vegas, the “Love So Soft” singer got emotional while praising Underwood for opening up about the three miscarriages she suffered before her current pregnancy with her second child.

“I’m so happy for her,” said The Voice coach, 36. “I didn’t know a lot of the situations that were going on behind the scenes, and I have a lot of friends that have gone through [miscarriage] several times as well.”

Clarkson recalled emailing Underwood, 35, to say, ” ‘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 that feel inferior, or feel like something’s wrong with them, it makes them feel comfortable, and [know] that [other] people go through it.’ ”

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Five weeks after her August pregnancy announcement, Underwood — whose second child on the way will join her and husband Mike Fisher‘s 3½-year-old son Isaiah Michael — revealed that she suffered from three miscarriages in the last two years.

“I’d kind of planned that 2017 was, you know, going to be the year that I work on new music, and I have a baby,” the “Cry Pretty” singer said earlier this month in an interview that aired on CBS Sunday Morning. “We got pregnant early 2017, and didn’t work out.”

At the time, Underwood leaned into her faith. “And that was the thing, in the beginning, it was like, ‘Okay, God, we know this … just wasn’t Your timing. And that is all right. We will bounce back and figure our way through it.’ ”

Carrie Underwood Honored With Star On The Hollywood Walk Of Fame
Carrie Underwood and Mike Fisher
| Credit: David Livingston/Getty

Carrie Underwood, husband Mike Fisher and son Isaiah

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After suffering a second miscarriage in 2017 and a third in 2018, “At that point, it was just kind of like, ‘Okay, like, what’s the deal? What is all of this?’ ” said Underwood, noting that she was “afraid to be angry” because of how “blessed” she felt with her family already.

But when she thought she might be suffering a fourth miscarriage, “I got mad,” the new Walk of Fame star recipient admitted to CBS News’ Tracy Smith.

One of Underwood’s most emotional moments came as she cuddled with her son and thought, “Why on Earth do I keep getting pregnant if I can’t have a kid? Like, what is this? Shut the door. Like, do something. Either shut the door or let me have a kid.”