Ms Tau's other sons were aged between 9 and 14, so she didn't have to worry about them, but she often babysat other under-5s.
"It's awesome because the mums can park their cars, put their kids over the fence to play and go and do their shopping without worrying either," she added.
No child in her whanau had been injured in a driveway, but she knew such tragedies had occurred in Kaikohe.
The programme began last November with the aim of reducing the risk of children being run over in the driveways of state houses by creating fenced-off play areas. Work will be done at another 25 Northland homes in the next few months.
Housing New Zealand Northland manager Neil Adams said the priority was to make safety improvements at properties where there were children aged 5 and under, as toddlers were at the greatest risk of being injured in a driveway accident.
The improvements ranged from installing fencing and self-closing gates with child-resistant latches to speed restriction signs, speed humps and convex mirrors, where appropriate.
"The work we carry out depends on the type of property, but the key priority is creating fenced play areas for children that are separate from the driveway," Mr Adams said.
"Ultimately we aim to complete 13,000 Housing New Zealand properties across New Zealand over four years."
Housing New Zealand also supported the work that Safekids Aotearoa, the injury prevention service of Auckland's Starship Hospital, was doing to prevent children being run over. According to Safekids, New Zealand has one of the highest recorded rates of child driveway death and injury in the world, with, on average, one child hospitalised every two weeks and five dying every year.
The majority of the children injured were toddlers, aged about 2, and their injuries were often severe. Most were run over by relatives.
Housing New Zealand provided driveway safety advice to people when they moved into a state rental home, and regularly included driveway safety information in newsletters to tenants, Mr Adams added.
Some simple safety behaviours could also help reduce the risk of accidents.
"Know where your children are before getting in the car, check for kids before driving off, and always supervise children around vehicles. Following these tips and making driveway safety improvements can definitely help save lives," he said.