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She will be walking down the aisle to marry fiancé Tom Pitfield in the Spring – and the couple's son Alfie will have a starring role on the big day as a pageboy.
"We wanted to wait until after his first birthday in March to tie the knot so he could be part of the big day," Catherine told HELLO!. "And from the way he's already trying to hold himself up, he should be walking by then."
Her Corrie co-star Antony Cotton will be one of her 'bridesmen' - and she says she has already picked up the perfect dress. "I've picked a gown that's totally unlike any design I thought I would choose," she said. "It's absolutely stunning – and I'll feel like the luckiest girl in the world when I wear it to make my vows to Tom."
Becoming husband and wife, she explains, is an important institution to her and Tom. "Marriage is forever," she said. "We don't take it lightly and we're both one hundred per cent together on that.
"Tom and I share the same old-fashioned values. Both our sets of parents are our role models when it comes to marriage."
Meanwhile, the couple are gearing up for their first festive season with Alfie, eight months.
"I've always loved Christmas but this one will be extra special and so much more important than ever before because Alfie is with us now," she said. Being a mum, she adds, is: "It's my best role ever, the best job in the world."