David Oliver's "parent radar" failed to go off when he and his family walked past a large dog sitting with its owner outside a cafe on Saturday.
Moments later he heard growling, followed by his wife's screams - and knew something awful had happened to his 4-year-old son, Ben.
"Leigh shouted, 'He's been bitten,' and Ben came running towards me with blood running down his face, down over his top. He was screaming, absolutely screaming."
The West Auckland family had been to the Titirangi village bakery and were walking home about 2pm when the attack happened.
Ben and his mother were making their way through tables on the footpath outside a cafe when Mrs Oliver noticed the bull mastiff-great dane cross sitting next to its owner, who was at a table.
Mrs Oliver said the owner smiled so she asked the lady what kind of dog it was. Then it lunged at Ben.
"It happened so quickly. The dog snarled and then leaped at his face like he was prey or something - with a lot of intent and a lot of aggression."
She remembers screaming and seeing her husband running towards Ben, but says the rest is a blur.
Mr Oliver said he was pushing his 20-month-old son, Alex, in a pram past the cafe when he heard the attack and turned to see Ben covered in blood.
"I picked him up and shouted, 'Somebody call an ambulance'."
He carried Ben into the cafe where staff helped put towels over the wounds in an attempt to stop the bleeding.
Mr Oliver initially feared the worst, and is haunted by the image of his son being attacked.
"That is the picture that just keeps coming back to me, him running towards me with the blood."
Ben had plastic surgery at Middlemore Hospital on Saturday night. He has about 20 stitches holding together four bites on the lower part of his face.
Speaking from his home where he is now recovering, Ben told the Herald the dog attack was "scary".
"It was bad, I felt the ache - it was sore, really sore. When the dog jumped up it still really hurted."
Ben's parents say there was no warning or indication something was about to happen before the attack
Ben was not provoking the dog or standing too close.
"Ben knows never to touch dogs. He was standing two metres away ... I was standing closer," said Mrs Oliver.
The Auckland Council will complete its investigation into the attack before deciding what will happen to the dog, which was registered.
* Auckland has had 328 attacks d during the past six months.
* Under the Dog Control Act, owners must keep their dogs under control at all times on public or private property.
* The Auckland Council's dog control bylaw is to be reviewed soon, and members of the public will be encouraged to make submissions.