Nappies, baby food, prams, clothing - when a baby comes into a family's mix there are a lot of additional costs.
It's especially tough for young mums or dads who want to study full-time to give themselves a better chance of a good job.
Danielle Van Meeuwen is one such mum. At the age of 23, she has started an accountancy degree. She loves it, and can see a good future ahead.
She was worried about losing the income from her job in a restaurant, but she'd done the maths and knew they could cope.
Husband Jonny was bringing home a salary from his job in double glazing,
Danielle would continue working part-time as a waitress and making baby clothes to sell in markets, and she would qualify for a full student allowance.
Or at least she thought she would.
She thought that was the case because she qualified for a full grant when she started her first degree.
Aged under 23, her grant was decided by her parent's joint income, which was below the threshold of $55,000.
Even when she got married, the grant stayed the same - still based on her parent's income.
So Danielle assumed it would remain the same once she had a baby.
However, when a baby comes along, the grant is then based on the joint income of Danielle and her partner, with a much lower cut off point.
Anything over $22,590 means no grant is available. Danielle was shocked.
The Ministry of Education confirmed this is the case, and explained other financial help was available.
This is true. Danielle qualifies for childcare support (not needed as she looks after her baby herself), accommodation allowance and family tax credit.
Danielle was very grateful, but all this help adds up to $6505 a year. Her student allowance was $9276 a year. So having a baby has left her $2770 worse off.
We quizzed the Ministry of Education about the fairness of this system.
They said, "As Danielle is now considered financially independent of her parents for the purposes of the student allowance, she is treated like every other student who is financially independent from their parents.
"Student allowances are intended to be a contribution to the costs of tertiary education, rather than to cover all of these costs. They are targeted to assist people in most financial need."
Fair Go thinks they are missing the point. If the allowances are to help those in most need, then Danielle should receive more help now she has a baby, not less.
They are not willing to change the system for her, but she's hoping that drawing attention to this discrepancy will help all the other young families who are trying to help themselves.