Carrie Underwood Calls Son Isaiah the ‘Best Big Brother’ on His 6th Birthday

Happy birthday to Carrie Underwood and Mike Fisher’s oldest son, Isaiah, who turned six years old on February 27. Underwood shared a touching tribute to Isaiah on social media, along with a picture of his elaborate Power Rangers cake.

“Today, we celebrate Isaiah…because today, he is 6 whole years old!” Underwood wrote. “Isaiah, you are kind, funny, smart, the best big brother, a lover of cuddles and crafts and you have the biggest heart and the best imagination! You love to make people feel good and you especially love to make them laugh! God has given you so many gifts and every day, I thank Him that I get to be your mom! I love you, Monkey! Happy birthday! And thank you, [Ivey Cake Store] for this epic Power Rangers cake!!! Yum!!!”

Fisher also spoke out about Isaiah’s birthday as well.

“Happy 6th birthday Isaiah!” Fisher wrote on Instagram. “I’m blessed to be your dad and proud of how you love Jesus and others so well! And please stop growing up so fast!!”

Underwood previously lamented how much Isaiah, who sang with his famous mom on “Little Drummer Boy,” for her My Gift album, was maturing and changing.

“I’ll make you real sad for a second: He now pronounces his ‘Rs,’” Underwood said (via ABC Audio). “He says ‘Pa rum pum pum pum’ when he sings it now, which is very sad for me. I mean, ultimately, you want them to pronounce Rs, but that moment is already gone, and it went like that.”

The American Idol alum was so proud to have Isaiah join her on her Christmas project.

“When I first heard it back I was laughing and crying at the same time because it was just this beautiful, pure moment from him,” Carrie told People. “He did such a great job. He remembered the lyrics and he sang it with his whole heart.”

Underwood’s  My Savior album, which includes “Softly and Tenderly,” and a duet with CeCe Winans on “Great Is Thy Faithfulness,” will be released on March 26. It is currently available for pre-order via her website.