Carrie Underwood shares how her son is preparing to be a big brother

Life is about to change for little Isaiah.
/ Source: TODAY

There comes a time in many a young child's life when they have to get ready for a big, life-changing moment: becoming ... a sibling.

Carrie Underwood, who is pregnant with her second child, isn't certain her 3-year-old Isaiah is quite there yet, but he's clearly working on it. And in the process, he's being awfully cute.

As she explained to "Tonight Show" host Jimmy Fallon Thursday, everyone is "excited to add to the family."

But Isaiah is only partly aware of what's going on. "I don't think for real he (understands)," she said. "He'll be really sweet and he'll like, talk to my belly and kiss my belly. He's the sweetest little boy."

She acknowledged that it's a strange moment for a first child, who's gotten very used to being the center of his parents' attention.

"I mean, no kid can really know that their life is going to change," she said. "He'll just have to share mommy."

Carrie Underwood performed "Love Wins" on "The Tonight Show" on September 13.NBC

Underwood has been married to Mike Fisher since 2010, and announced her second pregnancy in August.

She was to have performed on TODAY Friday, but the concert was canceled due to the network's ongoing coverage of Hurricane Florence.

As to her other upcoming special event, Underwood says she and Fisher have solicited Isaiah's advice on at least one critical issue.

Carrie Underwood talked about baby No. 2 with Jimmy Fallon.NBC

"We did ask him (if he had a name suggestion) and he did say, 'Isaiah Michael Fisher,' which is, of course, his name which, of course, would be confusing," Underwood laughed. "He wants to name everything his name because he thinks that's special."

It sure is!

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