The couple have spent the day celebrating Kai's seventh birthday and shared the excitement with fans by posting a sweet snap of the youngster and his brother Klay on Twitter.
However, although they spelt the caption correctly, the board standing alongside Kai's football cake in the picture contained an unfortunate blunder. It read: "HAPPY BIRHTDAY KAI." Oh dear!
Despite the mistake, the sentiment was definitely there and Coleen told her followers: "Our big boy is 7 today!!! Happy Birthday Kai, we love you xx." Footballer Wayne retweeted his wife's post.
Childhood sweethearts Coleen and Wayne married in Italy in June 2008. They welcomed Kai into the world 17 months later. The couple are also parents to three-year-old Klay and Kit, nine months.
Despite their millions, Coleen and Wayne are firm believers of discipline, especially as they wish their three sons to grow up just as they did.
Coleen recently told Now magazine: "They're all bathed and in bed at a certain time. And homework too - I'm strict on that with Kai. We're strict when we need to be.
"But during the summer holidays they're allowed to stay up later. But we want to keep them as we are, down to earth."
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