Katharine McPhee guests on Monday’s edition of “The Kelly Clarkson Show”, and the new mom gushed about recently welcoming her first child, son Rennie, whom she shares with husband David Foster.

“He’s such a good little baby and I’m so in love,” declared McPhee in a sneak peek at her appearance on the show. “It’s my greatest job I’ll ever have.”

Veteran mom Kelly Clarkson, however, cautioned McPhee that “the hardest thing for me is when they’re so freaking cute and you love them so much, but they’re doing something that’s naughty, right? And you’re like, ‘Nope, you will not twist me around your finger.'”

Weiss Eubanks/NBCUniversal
Weiss Eubanks/NBCUniversal

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“My girlfriend was doing my hair today. She was like, ‘Oh, can you even imagine you’re going to get mad at him one day?’ I’m like, ‘No, he’s so sweet right now, I can’t imagine,'” McPhee observed.

“Trust me, it’ll happen,” replied Clarkson. “And you’ll go, ‘Whose child are you exactly?'”

Katharine McPhee - The Kelly Clarkson Show
Weiss Eubanks/NBCUniversal

McPhee’s full appearance can be seen on the Monday, April 5 edition of “The Kelly Clarkson Show”.