"FIxer Upper" star Chip Gaines vowed to cut his hair if fans donated to St. Jude Children's Research Hospital -- and he stuck to his word, revealing his newly-buzzed head on social media.

On Wednesday, Joanna Gaines shared a photo of her husband's newly bald head on Instagram along with the caption: "We are leaving Memphis changed. Kiddos of @stjude we go with your faces on our minds and your stories in our hearts. Thank you for letting us be a part of your home at Target House. We are cheering you on every step of the way."

In the photo, young patients can be seen rubbing the top of Chip's head as the father of four grins widely.

Chip made the promise in an Instagram post last week: "Next week, Jo and I are visiting the beautiful kids at Target House with St. Jude Children's Research Hospital in Memphis," he wrote. "No family ever pays @StJudefor treatment, travel or food - so basically, we want to bring them a giant check from YOU to help cover costs - lets come together to do something big to bless these kiddos."

He added, "Donate to St. Jude through the link in my profile, and the more money we raise over the next FOUR days, the shorter my hair goes. That's a promise. And, who knows, maybe if you really exceed my expectations...I'll buzz it all off."

This is not the first time the Christian couple has engaged in a charitable endeavour. A portion of the proceeds from their newly-released Hearth and Hand collection for Target will be used to help families in need.

"One of the main reasons we decided to team up with Target is because we have found them to be the gold-standard when it comes to generosity and giving," Chip announced in a blog post. "This really resonates with us. Jo and I believe that to whom much is given, much is required. As our platform has grown, so has our desire to help communities far beyond Waco, Texas."

He added, "About a year ago, we decided to create the Magnolia Foundation to help local communities and families in need all over the country. With Hearth & Hand with Magnolia, we'll work with a number of charities to roll up our sleeves and get to work with."

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