Happy birthday, Hudson London Anstead!
"Happy birthday Hudzo!! 🎉🎊Where has the year gone!???" Ant, 41, wrote alongside a slideshow of photos and videos of Hudson. "You are our miracle baby, the perfect blend of your beautiful mummy 🥰 and this Brit dad 👴🏼! We love you so much! Today we celebrate you! 🇬🇧🇺🇸❤️."
Related: El Moussa is 'so happy' his kids get along with Ex Anstead's newborn
The Wheeler Dealers star said that he "always found it weird (cool)" that his two older children, Amelie, 16, and Archie, 13, whom he shares with his ex-wife Louise Herbert, have birthdays that are seven days apart. Christina's son Brayden James, 5, and daughter Taylor Reese, 9, whom she shares with her ex Tarek El Moussa, also have their birthdays a week apart.
"Coincidence? I don’t think so!" Ant said, before writing out the dates that all of his and Christina's children were born.
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Christina, 37, also shared a slideshow of adorable footage of Hudson, writing, "Happy 1️⃣ Birthday Hudson! Sweet, sensitive, busy boy ... can’t wait for you to be chasing your siblings around the house soon 😎 - we love you 💙."
Last summer, the mom of three told PEOPLE she was excited about blending her family with Ant’s children.
“It’s so amazing that we get to raise a child together,” Christina said at the time. “All of the kids are so excited. I love all the fun chaos and a full house. I always thought I would only have two, and now I’ll have five!"
Ant shared his “golden rule” for merging households when speaking with Entertainment Tonight last October, explaining that “everybody has to be on the same page.”
“Everybody has to be present and pulling in the same direction. That includes Tarek, it includes my ex,” he said at the time. “If everybody wants the same thing, and that has to be kids first. If you prioritize kids first, it actually kind of falls into place and the rest of it makes sense.”
Anstead added: “If you ever make a decision that doesn’t put the kids first, it is the wrong decision."