"He'll be really sweet and talk to my belly and kiss my belly. He's the sweetest little boy. But no kid can really know that their life is going to change... He'll have to share Mommy," Carrie Underwood told Jimmy Fallon

Carrie Underwood is having another baby, and she’s not sure if her first child is quite ready for it.

The “Love Wins” singer, 35, shared how her 3½-year-old son Isaiah Michael is dealing with the news while appearing on The Tonight Show Starring Jimmy Fallon on Thursday night.

“[Isaiah] is absolutely amazing,” the American Idol alum began. “We’re excited to add to the family.”

When Fallon, 43, asked if Isaiah understands he’s going to be a big brother, Underwood responded, “I don’t think for real he does.”

The Tonight Show Starring Jimmy Fallon - Season 5
Carrie Underwood and Jimmy Fallon
| Credit: Andrew Lipovsky/NBC

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Carrie Underwood and Isaiah
| Credit: Mike Fisher/Instagram

She continued, “He’ll be really sweet and talk to my belly and kiss my belly. He’s the sweetest little boy. But no kid can really know that their life is going to change… He’ll have to share Mommy.”

In an interview with The Tennessean published back in August, Underwood said being a mom of two is “going to be a different ball game, for sure. My brain, I’m such a planner. I want to know how it’s all going to go. But no matter who you are, you make it happen, you make it work, you get your team behind you.”

On Friday, Fallon also wondered if Underwood and her husband, hockey player Mike Fisher, asked for Isaiah’s opinion about the baby-to-be’s name.

Carrie Underwood and Mike Fisher

“We did ask,” Underwood answered, adding “and he said ‘Isaiah Michael Fisher,’ which is, of course, his name, which, of course, would be confusing.”

She explained, “He wants to name everything his name cause he thinks that’s special.”

Mike and Isaiah Fisher
| Credit: Carrie Underwood/Instagram

The upcoming CMAs host also divulged that she’s already scoping out her toddler’s singing ability and hoping he’ll take after his mom.

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“I’m judging my 3½-year-old child,” she joked. “If he’s not musically inclined that’s fine. I’m excited to find out what he loves and is passionate about and is good at, and I will support that. But I really want him to sing.”

When it comes to musical taste, Isaiah is currently all about the throwbacks. According to Underwood, his favorite songs are the Fraggle Rock and Duck Tale themes.

Carrie Underwood and son Isaiah
| Credit: Carrie Underwood/Instagram

In addition to announcing her second pregnancy last month, the Cry Pretty producer also experienced another big milestone recently. Earlier this week, it was announced that she would receive a star on the Hollywood Walk of Fame. She’ll be the 2,646th celebrity to do so.

Carrie Underwood

The honor will commemorate Underwood’s 13-year-career in the music business, which has seen the Oklahoma native win dozens upon dozens of awards — including seven Grammys, six CMAs and 14 ACMs.