"My fiance and I checked on our sons more than usual on Sunday night. I wanted to know they were still in their beds," she said.
The woman had gone to the dairy with friends and had her hands full as her son walked along beside her.
Two friends and a child walked ahead and sat on rocks outside The Barrel liquor store.
The mother had turned to look at her son, who was throwing a tantrum, and did not see a man come up behind her.
Her friends called out and when she turned around the man was very close.
"I looked around and went back to grab my son.
"The man then tried to get between me and my son," the woman said.
Every time he did this, the mother prevented him getting between them; and every time she did this, he went around her to get between them again.
The woman said the man had what she thought was a cannabis cigarette in his hand, and she also believed he was under the influence of drugs because "his pupils were pinpricks and he was very jumpy".
The man is described as having ginger hair and freckles, very dirty jeans and filthy bare feet.
One of the woman's friends came and picked up the 2-year-old and the man ran to an old-model black van, with a tinted back window and three grey stripes down the side, parked outside the fish-and-chip shop.
The woman said two middle-aged people, whom she thought were of Pacific Island descent, were seated in the van.
The driver was a man of big build and the female passenger wore a red shirt and sunglasses. Both of the van's front windows were down.
The people in the van watched the group walk a few metres down the road and then drove off.
The woman said she had never seen the man before, or the van.
She waited until she got home to call police, who arrived within minutes.
Police advised that she should have called 111 at the time of the incident, because the delay might have been the difference between arresting the man and his escape.
Mr Brunger said anyone with any information should contact the police, phone 06 349 0600.
