Clarkson revealed to Entertainment Tonight that she reached out to her fellow "American Idol" winner to tell her how important it was for her to publicly talk about the three miscarriages she suffered before her current pregnancy with her second child.
"I'm so happy for her," the "Voice" coach, told ET at this weekend's 2018 iHeartRadio Music Festival in Las Vegas. "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."
The "Stronger" singer revealed she sent Underwood, 35, an email telling her how much she helped other women when she shared her painful story.
"'It’s so important that you talk about it'," Clarkson recalled writing Underwood. "'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.'"
But one night, when she thought she might be suffering a fourth miscarriage, she allowed herself to get mad. "And for the first time, I feel like I actually told God how I felt,” she said. “That was like a Saturday — and the Monday I went to the doctor to, like, confirm, another miscarriage. And they told me everything was great."
In August, Underwood shared her happy pregnancy news via a sweet two-part Instagram video that began as an announcement for her Cry Pretty Tour 360, but then switched gears into more personal terrain.
“You might be wondering or asking, 'Carrie, why is your tour starting in May?'" the singer asked fans in her video. The camera then pulled back to reveal four balloons behind her spelling out B-A-B-Y.
"Mike and Isaiah and I are absolutely over the moon and excited to be adding another little fish to our pond," she gleefully shared, calling it a "dream come true."