Lifestyle Health Pregnant Joanna Gaines 'Couldn't Be Prouder' of Husband Chip as He Prepares for First Marathon While Chip Gaines is hard at work training for his upcoming marathon, he can count on his wife, Joanna Gaines, to always have his back By Alexia Fernández Published on May 5, 2018 12:15 AM Share Tweet Pin Email While Chip Gaines is hard at work training for his upcoming marathon, he can count on his wife, Joanna Gaines, to always have his back. The pregnant mother of four, 40, shared a sweet photo of her husband, 43, running on Instagram in preparation for the Silo District Marathon in Waco, Texas, on Sunday. Aside from being his first ever marathon, the event is actually being hosted by Chip and his wife to raise money for the Brave Like Gabe Foundation to fund research into rare cancers and their treatment. Joanna shared why Chip – who was pictured wearing dark workout clothes and a headband in his hair as he ran along a gravel path surrounded by trees – decided to run and host a marathon. “It all started with a lofty goal that he first considered while writing his book Capital Gaines,” she wrote in the caption. “Then last October Chip randomly ran into [professional runner and cancer survivor Gabe Grunewald] in Central Park where she shared some of her story. It was then that Chip was inspired to take this goal of running a marathon and turn it into something bigger: raising money and awareness for rare cancer research.” She continued, “This weekend 6,000 runners from all 50 states and 7 countries will participate in our first annual #SiloDistrictMarathon right here in Waco, TX. All profits from this race will go to her foundation @bravelikegabe.” “Chip, I couldn’t be prouder of you. I am thankful for your big heart and big vision. Go get ’em this weekend, and you better believe I’ll be the first in line at the finish to give you the biggest hug!” Joanna added. “#yourbiggestfan#yougotthis #26.2miles.” While Joanna was cheering him on, Chip is also a big fan of his wife. Before she made an appearance at the Today show in April, her husband stood among a crowd of fans with a sign that read, “I [heart] Joanna Gaines!” Chip shared the full video on his own Instagram, where he was caught jumping up and down and exclaiming, “Where is she!?” and “Have you seen her?!” to his fellow Joanna supporters. Perry Hagopian The duo is currently expecting their fifth child together — a boy – this summer. They are already parents to sons Duke, 9, and Drake, 13, as well as daughters Emmie, 8, and Ella, 11. Joanna says the pregnancy came as a total surprise in the latest issue of PEOPLE. “I had been feeling a little emotional and crazy and thought, ‘Wow, this isn’t me,'” she says. “Then all of a sudden I realized, ‘Hey, I remember this.’ When I saw the results of the test, my jaw dropped.” RELATED VIDEO: In PEOPLE’s The Best of HGTV Special Edition Get Up Close with Your Favorite Renovation and Real Estate Stars She continued, “Chip was in the driveway about to leave when I called him back and said, ‘We’re pregnant!’ He was so excited. We’re both just so excited.” The former Fixer Upper star also revealed how her four older children were reacting to her pregnancy. Want to keep up on the latest from PEOPLE? Sign up for our daily newsletter to get our best stories of the day delivered straight to your inbox. “Every single time they see my belly they have to rub it,” she says. “I think it’s sweet because they’re older now, and I can see them wanting to be a part of this. We’re all rallying around this baby, which I feel is a sweet gift to our family.” For more on Chip and Joanna Gaines’ baby joy and her new cookbook, pick up the latest issue of PEOPLE, on newsstands now.