Mrs Van Wonderen hoped that Emily's punctuality was a trait she would hold onto as she grew up. "Time will tell," she said.
Emily's older brother, Willem, met his little sister for the first time yesterday, which his parents said went "very well".
"He just wanted lots of cuddles," Mrs Van Wonderen said from Birthcare in Parnell.
Mr and Mrs Van Wonderen, both 29 and of Ellerslie, have yet to decide whether they'll add to their brood. "Two's good for us at the moment I think," Mrs Van Wonderen said.
Population statistics manager Andrea Blackburn said: "The 1.5 millionth person could be a migrant coming from overseas or from within New Zealand but it is most likely to be a new baby."