"And my partner Sarah said, 'yeah, I'm feeling twice as sick as last time'."
At the time he told the Herald his preference would be to have twin girls, as they already have 19-month-old son Brando.
"I think I've got a preference ... I've got a boy so it would be amazing to have two girls.
"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."
By the time the twins arrive early next year, the parents will be caring for three children under 3.
"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 explained, noting that he wants the twins to be able to define themselves and form their own individual identities.
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 twins are due early February next year.
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