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"We found out Gi was pregnant the night we were going to Disneyworld on holiday," Tom told HELLO!. "Then it was awesome because we were walking around Disney looking at families and kids everywhere and being like ’Awww. That's going to be us.' We are so excited.'" Their baby is due at the end of March.
It was the couple’s first appearance together since officially announcing that they were expecting a baby, which they did via a cute YouTube video clip that has already had more than a million hits.
Added Gi, "It was really early when we found out. We did the test because we wanted to know for going on big rides, so it was like early one morning, and it was positive! You start to see everything in a different way... so we were taking in the magic of being at Disney rather than just going from ride to ride."
Tom says he came up with the idea for the video, which used a message carved in pumpkins to announce their happy news, while Giovanna was on holiday in Dubai.
"We knew people were going to guess so we had to say something," he said. "Gi was away for two weeks so I had plenty of time to come up with ideas."
The singer-songwriter admits he is now getting into dad-to-be mode. "I am so overprotective already," he laughed. "I'm thinking about getting a really big car, like a tank, to be safe in."
The couple have decided not to find out if they are expecting a boy or a girl, and told HELLO! that their families are thrilled at the news. "I think we'll struggle to see our own kid as our parents are so excited," said Tom.
He has always been a massive Disney fan. "I grew up loving it. Gi hadn't been to Disney until she met me," he said. "We went on our honeymoon there, and stayed at the Grand Floridian, wore the Just Married badges, and everyone was congratulating us," added the McFly singer.
Also enjoying the fun at The Disney Store in Oxford Street was pregnant Michelle Heaton who was getting in some early Christmas shopping ahead of the birth of her son with husband Hugh Hanley in March. Michelle was with daughter Faith who wore a Minnie Mouse T-shirt.
Denise Van Outen and her daughter Betsy where getting into the magic of Christmas, with Denise wearing a Minnie Mouse ears and a spotted jumper dress by Very, and Betsy looking super cute in a Cinderella gown, pretty princess pumps and carrying a Minnie Mouse handbag.
Minnie and Mickey put in an appearance too, arriving at the Oxford Street store by horse-drawn carriage with snow falling around them. Jo Whiley, Meg Matthews, Elen Rivas, Donal McIntyre, Kate Garraway also attended the magical evening.