Carrie Underwood's son, Isaiah, just celebrated his fifth birthday, and his party really took the cake. The country superstar turned to social media to share a picture of the special Scooby-Doo-themed cake she had made for the occasion.

The elaborate cake features the Mystery Machine at the top, with Shaggy holding Scooby in his arms in a classic pose that usually happens when the canine sleuth gets scared — which is pretty often. The rest of the cake features a haunted house, a bat silhouetted against the moon and what looks like a zombie chasing down some of the other members of the crime-solving team.

"The cake was beyond amazing and all the kiddos left full and tired out!" Underwood writes to accompany the photo. "Tonight, when Isaiah was saying his prayers he thanked God for all of his friends and for the wonderful day he had...that made it all worth it!" she states, adding a smiling emoji and a series of hashtags.

Underwood also thanked a Nashville-area trampoline park called Defy Nashville, as well as a business called Ivey Cake, which created the specialty cake. One of Underwood's closest friends, Ivey Childers, started the business, and she has created a series of cool confections for various special moments in Underwood's life for years.

Childers was actually hired to make a cake for the celebration when Underwood won American Idol, but the two didn't meet in person until she began dating Underwood's bass player and bandleader, Mark Childers, several years later, according to CMT. They have since become very close friends, and Childers designed the impressive cupcake tower that was featured at Underwood's wedding to Mike Fisher in 2010.

Underwood previously turned to social media to reflect on Isaiah turning five on Feb. 27, writing, "Isaiah, you are funny and smart and such a caring little boy! You already have so much love for God and for all those around you. The day I became your mother was the day my life changed forever. You are five today but you will always be my baby matter how old you get. Thank you for being you."

Carrie Underwood and Mike Fisher's Sweetest Pictures Together:

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