Carrie Underwood Shares the Sweet Cards Her Sons Isaiah and Jacob Crafted for Her 40th Birthday

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Carrie Underwood is getting some birthday love from her two sons.

The "Denim & Rhinestones" singer posted a pair of cute photos on her Instagram Story Friday of two letters her sons wrote to celebrate her on her milestone 40th birthday.

"Things Jake loves about me…" Underwood wrote with her first post, alongside three heart emojis and a picture of 4-year-old son Jacob Ryan's note. The paper, sweetly titled "Things I love about mommy," listed things such as, "When she kisses me," "How much she loves me," "She's beautiful," "Her snuggles" and "When she dresses up."

In the next slide, Underwood wrote, "4 Things Isaiah loves about me" with a snap of her 8-year-old son Isaiah Michael's letter. In the note, which read like a poem, Underwood's oldest wrote, "4 Things I Love about Mommy! I love her snuggles, I love her kisses, I love her singing and most of all I love her love!"

Underwood also shared some other photos on her Instagram Story as well, including one of a birthday cake tower that was "made entirely of cheese wheels," and a bunch of wines "starting from 1983" placed in a row behind it. She joked that she "felt understood."

"For size context… I believe this is about 70 lbs. of cheese!" the mother of two captioned a selfie with the cake — which featured a "Happy Birthday" topping, as well as additional decorations on the cheese wheels, such as green grapes, figs and flowers.

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Earlier in the day, Underwood shared how she began her birthday with a photo of an omelet, raspberries and a slice of toast on a plate. She captioned the post, "Breakfast in bed...."

Shortly after, her husband, Mike Fisher, dedicated a sweet birthday tribute to the singer on Instagram.

"Happy birthday babe!! The boys and I love you so much!! #happybirthday," wrote Fisher, 42, alongside a photo of Underwood posing with her five-tier birthday cake.

RELATED: Carrie Underwood Shows Off Adorable Pillow Her Two Sons Designed for Her Tour Bus: 'New Decor'

Underwood also surprised fans with a new song on her birthday, titled "Out of That Truck."

"Had some fun in the studio recently and for my birthday, I wanted to share my new song 'Out of That Truck' with all of you! 🥳," she wrote on Instagram.

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In the post, Underwood shared a behind-the-scenes video of the recording process, where she spoke about the song's inspiration.

"It was like having this memory, [a] nostalgic kind of song, where it's like you kind of can't get over somebody, but it's because of all the physical marks that you left in a space, being the truck," she said, adding that some of those physical marks are "nail polish on the tailgate" and "dings on the door."