And if there was no surviving parents and no will family members would also have to apply separately for guardianship of the children.
Lockhart said even those who did not have assets should write a will to determine who would take care of their children should the worst happen.
"If you don't appoint a guardian for your children it may end up being someone who you don't want."
Likewise leaving it to chance may mean your assets are not be distributed as you wish.
In the case of a parent dying without a will the first $155,000 goes to the surviving spouse as well as a third of any remaining money while the other two thirds is held in trust for the children until they turn 20.
Lockhart said that situation could put undue financial pressure on the surviving spouse as some of the money would be locked up when it could be better used elsewhere.
Of those who did not have a will 32 per cent said the biggest reason was because they had not got around to it while 16 per cent said it was because they did not have enough assets.
For those with a will 55 per cent wrote it more than five years ago with 34 per cent doing it more than 10 years ago.
Lockhart said having an out of date will could be just as damaging as not having a will and she urged people to regularly update them.
She said changing relationships and life stages were good reasons to have another look at your will.
Just 8 per cent of people surveyed said they were relying on an inheritance to ensure their financial stability later in life.
But it looks like some people will be in luck when it comes to inheriting.
Of those who have a will 16 per cent planned to leave more than a million dollars to their family while 24 per cent would leave between $500k and $1 million and a further 38 per cent would leave under half a million dollars.
The research surveyed 1223 adults aged 24 to 69 throughout New Zealand.