The technician conducting the scan had big news to share with the couple. The reason Bowman was feeling so nauseous was that she was expecting identical twins.
"We just about fell out of our chairs and I had to go for a walk," Wallace admits, sharing how he first coped with the news.
"It's a massive refocus in terms of what I'm doing with my life," Wallace says.
The couple has a 19-month-old son Brando, so by the time the twins arrive early next year, the parents will be caring for three children under 3. It will be a bit of an adjustment for Wallace, who is used to living life at a bit of a slower pace.
"I'm normally a slow mover, I still live in the same house that I bought, I think we've been in it for eight years. Within a week we've decided to sell it, and we're in the process of trying to buy a new house right now," He lists off the boxes he has to tick before the babies arrive: Finding a new house and upgrading his current vehicle among the items.
"It's been a lot of changes. It's pretty much turned our whole world upside down for the best possible reasons ever, so that's exciting."
It's a joyous moment for the couple. They decided to share the news with the public early on in the pregnancy. Wallace says all test results so far show the pregnancy is "on the right track".
Before having their first son, Wallace and Bowman sadly suffered a miscarriage at 17 weeks. "We've been through a pregnancy that didn't work out, and we were left on our own because no one knew," Wallace explains. "So we're happy to share this news and have our friends and people along to support us along the way."
Wallace had two important people to share the news with, his son Brando and his co-presenter Toni Street. He shared the news with his co-host, teasing part of her reaction on Instagram on Friday. He will have to wait a bit longer to gauge his son's true feelings about his new siblings.
"We've told [Brando] but he doesn't really understand because he's quite young. He's in for a hell of a shock because at the moment, the whole world revolves around him, and very soon, he's going to have to take a little bit of a back seat as we kind of learn how to deal with twins."
So how does a parent prepare for twins? The couple have been doing a lot of research and crowd-sourcing information from other parents who have twins.
"The advice that we've been passed on is that it's really important to make sure they get their own identity. It's really cute to dress them the same and we will probably do a bit of that, but we'll work really hard to ensure that we will separate them as much as we can," Wallace explains, noting that he wants the twins to be able to define themselves and form their own individual identities.
The couple is keeping the genders a secret for now - but Street will be the first to know, as she's responsible for the epic gender reveal where she will paint the wall blue or pink depending on whether the twins are boys or girls. For now, the news remains sealed in an envelope.
"That's the perfect family but all I really want is us to have healthy twins and I really don't care if I've got three boys.
"We'd be on a way to my starting five basketball team, and we'd have some pretty amazing motocross days but yeah, the perfect balance would be a couple of girls as well."
Wallace says being a parent is a lesson in patience. "There's nothing harder.
"I think that when you have lived life as I have, working in the media since I was very young, I've always been the centre of attention. So to shift that focus away from me and on to them [children] has been the best thing that's ever happened to me."
Wallace and Bowman's identical twins are due early February next year.
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