"Happy birthday babe!!" he declared via a Friday, March 10, Instagram post, which showed the singer flashing a smile next to bottles of wine and a tiered cake made out of cheese wheels.
"The boys and I love you so much!! #happybirthday," added the athlete, referencing their two sons, Isaiah, 8, and Jacob, 4.
As OK! reported, the dad-of-two was allegedly feeling neglected as she continued to put her career and life on the road before their marriage.
"She used to be paranoid about him when he was playing ice hockey and traveling around with the team with all those groupies hanging around," shared the source. "Now he's paranoid about her being so many miles away."
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"It's not the happy home they make it out to be," the source added. "Mike's feeling a little under-appreciated. Carrie does tend to be self-involved, so it's up to her to make him feel cherished."
In addition, the blonde beauty's dedication to performing has caused the retired hockey star to put his own aspirations on the back-burner.
"Mike gets a lot of offers to go into coaching. But when he brings it up to Carrie, she says absolutely not. She reminds him when he was playing, traveling all over North America, they barely saw each other," another insider spilled. "You just feel if the two of them can't reach a happy medium in their personal and professional lives, their marriage is doomed!"
However, Underwood has been trying to change her ways, as she revealed in October 2022, "This tour, I’m going home a lot more than I ever have before. If there’s a way to get me home, even if it’s just for the day [I'll do it]."