"I felt my heart literally open up for the first time and wrap itself around her. It was profound," Applegate told People. "And I'm more in love with her every minute of the day."
Applegate, who had a double mastectomy to fight breast cancer back in 2008, was more than ready to focus on something -- or someone -- more positive.
"I've had to talk about that word more than I've ever had to talk about a word in my life," she says of cancer. "After a while you're like, 'There's got to be something else to me.'"
Now, instead of fighting the fight and talking the talk, the Anchorman star, 39, is busy playing mom, with baby daddy LeNoble, 41, by her side.
"She's healed me in so many ways. She's just made my life so much better. She's opened my whole soul," Applegate said. "I want to be the ultimate burper and diaper-changer, I want to be the ultimate at all of it.
"Sometimes I stand there going, 'I'm not doing any of this right!' And then I get this big man belch out of her and I go, 'Ah, we accomplished this together.'"
SheKnows sends congratulations to the new parents and a big welcome to little Sadie!
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