Millie and Katherine have been best friends since they were 3 years old.
Singer Amy Grant is one proud mom after her daughter saved her best friend's life by donating a kidney.
"I was proud of her for a lot of things," Grant told Inside Edition. "This is just in a realm all in its own."
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The singer’s daughter, Gloria “Millie” Chapman, 23, met Katherine Dudley when they were just 3 years old. They've been as close as sisters ever since.
Katherine suffers from a degenerative kidney disease. She's known for years that she would one day need a kidney transplant, and when the moment came, Millie didn't blink.
"She has always been a part of my life," Millie told Inside Edition. "I can’t remember when she hasn’t. I didn’t even think about it, it was, "Of course I will give you mine."
As luck would have it, Millie was a match. Her kidneys were also incredibly healthy.
Grant was understandably nervous on the day of the surgery, saying, "I think I was probably more afraid than I let on."
Fortunately, the January 23 transplant went off without a hitch.
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It's only been five weeks since Millie gave her friend the gift of life. For Grant, it's only confirmed what she already knew about her daughter.
"I can’t imagine being more blown away than anything she would ever do," Grant said.
Watch: Preschool Teacher Recovers After Donating Kidney to Student: 'I Wanted to Give Lyla a Future'
