"One of the girls started to lose a little bit of weight which meant we had to introduce some tube feeding which has done the trick.
"The girls are doing amazingly well."
And Wallace said the support from staff at North Shore Hospital has been "amazing".
"They've been incredibly supportive, just fantastic."
He said mum Sarah was "going great" despite the constant feeding.
But the radio host says finding names for the twins is proving to be a "tough ask".
"I reckon naming girls is harder than boys.
"You want a name that's cute but you also want a strong name too which is equally important."
They have a couple of sets of names picked out, he said, but have yet to decide on the winning combo.
And he revealed that 2-year-old son Brando is adjusting well to his new siblings so far.
"Brando has been super cute. He gave them these beautiful little kisses when he met them," Wallace said.
He and Bowman tried to prepare him for new siblings by giving him some dolls to play with.
"The dolls seemed really small when he was playing with them, but then when the twins turned up, they were even smaller, just so tiny."
Sounds like Brando will be a great big brother, as his dad shares he's "getting the idea of 'soft hands' really quickly".
