The former Emmerdale actor, who won Strictly with Oti Mabuse back in 2019, shared the happy news on Tuesday, and admitted the couple were "extremely grateful".
WATCH: Kelvin Fletcher & wife Liz play Hello/Goodbye
He told PA news agency: "There's no question that for the Fletcher family the best thing to come out of 2021 is the news that we are expecting again. We are feeling extremely grateful and can't wait to meet the new addition to our family."
Kelvin married fellow actor Liz in 2015, having first met as children, and then reuniting around a decade ago. They are already doting parents to two children, Marnie and Milo.
Last year, the couple spoke exclusively with HELLO! about family life which included homeschooling their daughter Marnie. "She's only three and at preschool, but it did feel daunting at first," said Kelvin.
"Liz and I feel a responsibility for our daughter's education. I've always had respect for teachers, but even more so now. Liz is a better teacher than I am. She is more structured and gets better results."
The couple with their two children, Marnie and Milo
"He's 100% correct," joked Liz. "Kelvin does not teach. Before you know it, they're in fancy dress or playing outside."
His recent downtime has given him a chance to experience some special moments with his children. "Marnie loves to dress up, but the next minute she'll want to get mucky and fix things with a spanner," added Kelvin.
"Both the children have an inquisitive nature, which is so pure, and we want to embrace that. If we all want to wear make-up, we'll all wear make-up.
"It's about having no boundaries or inhibitions. I think that's the best way a child can learn, and hopefully grow up with no preconceived ideas and be free to be who they want to be. Milo has certainly got a good role model in his big sister."
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