Chip Gaines celebrates wedding anniversary by penning a sweet poem to wife Joanna

Happy anniversary, Chip and Joanna Gaines!

The Fixer Upper stars celebrated 15 years of marriage on Thursday, and in honor of their special day, Chip shared a sweet poem he wrote for his wife via Twitter.

"15 years.. where'd they go. 15 years.. I’d like to know," he wrote. "15 more, to God I pray. 15 more just to make her day. Happy anniversary sweet girl!"

Joanna followed suit, posting a stunning black-and-white shot from their wedding day to her own account.

"It's been a good fifteen years @chipgaines," she captioned it. "Here's to fifty more..."

Chip, 43, and Joanna, 40, tied the knot on May 31, 2003. They share four children -- Drake, 13, Ella, 11, Duke, 9, and Emmie Kay, 8 -- and are expecting their fifth child, a baby boy, this summer.

When ET caught up with Joanna last month in New York City, she gave us an update on how her pregnancy has been going, admitting she's been craving a lot of sugar lately.

"Anything a 5-year-old or younger would love is what I am craving right now, which is so weird!" she joked. "For Drake, [I craved] ice and lemons, so I always made Chip go to the gas station late at night to get the crunchy ice because we didn't have that in our fridge. With the boys, it was always something citrusy and right now, I am craving oranges and lemons. And then [with] the girls, [I wanted] salty. I normally don't crave citrus, but I have to have an orange every day now."

See more photos of Chip and Jo together:

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