Carrie Underwood Says 'Time Flies' as She Celebrates Son Isaiah's 9th Birthday with a Taekwondo Party

Carrie Underwood's son is celebrating a special day.

On Sunday, the country singer, 40, shared a series of photos to her Instagram of her son Isaiah's birthday cake, honoring her little guy as he turned 9. The sweet treat featured a taekwondo student on top, kicking in the air as the cake read "Takewondo Martial Arts Isaiah Fisher."

"Today, we got to celebrate our sweet Isaiah turning 9!!!! Oh, how time flies…we got to party doing one of his favorite things…taekwondo!" Underwood wrote in her caption.

"So fun to see the kids learning some new things. And what an amazing cake from @iveycakestore !!! It was as yummy as it was cool!"

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Underwood shares her sons Isaiah and Jacob, 5, with husband Mike Fisher.

In January, the musician shared scenes from a very special birthday for son Jacob, who turned 5. The birthday boy enjoyed a little nighttime fun at the family's Nashville home, where frigid temperature made for perfect ice hockey weather.

"A special birthday for a special 5 year old!!! Our pond was frozen over in perfect condition for a night skate!" she shared. "What a treat!!! Happy birthday, Jake! I know you wouldn’t have wanted it any other way! #blessed #hockey #12 #HappyBirthday #DudePerfect."

The week prior, Underwood showed that Jacob was all about the winter weather, sharing a photo of her younger son peering out a window at a snowy garden.

Jacob hoisted himself up to peer between the window panes to look at the snow-covered plants in the musician's hometown of Nashville.

"❤️❤️❤️❄️❄️❄️," Underwood wrote across the picture.

During an appearance on Today in October 2022, Underwood opened up about the fact that Isaiah was starting to pick up that his mom is famous.

"I feel like, Isaiah, who's seven and a half, he's becoming more aware that it's not normal," she said.

"He'll go to school and someone will be like, 'I saw your mom on TV last night.' " Underwood added, "He's just becoming more aware that his mom does something that's not normal."