Carrie Underwood Sings With 5-Year-Old Son Isaiah for 'My Gift' Christmas Special

Carrie Underwood and Son Isaiah

The songstress shared a special musical moment with her little boy.

Carrie Underwood is gifting fans with some serious Christmas cuteness. The celebrated songstress decided to turn to her adorable son to sing a duet on her new album, My Gift -- and the recording is featured in her new streaming TV special.

Underwood took to Instagram on Tuesday to share a sweet snapshot of showing her singing with her 5-year-old son Isaiah as part of her new My Gift: A Christmas Special From Carrie Underwood, which dropped on HBO Max on Thursday.

"So happy we captured the sweetest voice in this special moment in time," Underwood wrote alongside the photo of herself and Isaiah recording their duet. The celebrated country crooner shares Isaiah with husband Mike Fisher, as well as 1-year-old son Jacob.

"My own Little Drummer Boy will be a part of the #MyGift Christmas Special beginning this Thursday on @hbomax! #MyGiftHBOMax 🥁🎁✨" Underwood added in the caption.

The adorable nickname is clearly appropriate given their duet is "The Little Drummer Boy," which Underwood recently told USA Today is "a central song" on My Gift.

"Thinking about what would make it special, I have a very special duet partner, my son Isaiah. He loves to sing," she shared. "I just thought his sweet little voice would sound perfect."

Apart from her collaboration with her son, Underwood also performs a duet with John Legend as part of the album and the TV special.

Together, the two perform a stunning rendition of "Hallelujah," as Legend plays the piano and an angelic Underwood joins him in belting out the emotional, stirring tune.

ET's Rachel Smith spoke with Underwood in October, and the songstress excitedly reflected on her collaboration with her little boy as part of the holiday album, which dropped in September.

"He loves to sing…and he has such a giving, loving heart about him and I could just hear his voice on it," she told ET, explaining how at first she didn't know if he would want to do it. "So he goes in there and he just gave it his all and it's so pure and it's so special and he's throwing his hands in the air and just so expressive when he was singing it."

"I was so proud of him, just for giving it his all and the love in his heart because he does love Jesus," she continued. "At 5 years old he knows, and he was giving all the love. I'm very proud of him."

My Gift: A Christmas Special From Carrie Underwood is available on HBO Max now.