After hearing cracking sounds she thought were branches breaking, Esme (12), persuaded her 8-year-old sister Lydia to leave the garden of their Malvern St home where the two were playing beneath a wattle tree.
Moments later, a wind gust broke the enormous tree off at its base, sending it crashing on to the area where the girls had been and through the roof of their house.
A trampoline and outdoor play kitchen area were flattened, and relieved mother Rochelle Wilson knows her daughters could have been killed.
"It's unbelievable the damage the tree has done."
Esme had tried to get her sister to move away from the tree, Ms Wilson said. When Lydia said she did not want to, Esme told her she would "play cakes with her inside". That was enough to get Lydia out of the tree's path.
"His basketball hoop is out there and he is usually out there, too."
Ms Wilson and her partner, Ken Knox, the children's father, have lived in the house for about two and a-half years.
Ms Wilson said the previous owners had told her they tried to get permission to fell the tree because large branches had fallen from it, but a neighbour objected to their resource consent application.
"The neighbour thought the tree added beauty to the neighbourhood when it was in flower. Look at it now."
The house was badly damaged along its entire western side. Both the wall and ceiling of Ms Wilson and Mr Knox's bedroom was caved in, while branches also knocked a hole in the dining room ceiling.
Neighbours rallied to cut tree limbs off the roof and help shore up the bedroom. Willowbank firefighters also attended.
Ms Wilson and her children will stay with relatives until the damage is assessed.
Mr Knox, an electrician, is working in Papua New Guinea in a gold mine but Ms Wilson rang him soon after the incident and emailed him photographs.
Ms Wilson said her daughters were "very upset" by their close call, but she was more philosophical once she found her daughters were safe.
"What's done is done. Insurance will hopefully take care of it."