Senators David Leyonhjelm and Pauline Hanson blame the childcare fee increases on the fact educators have to be certified. Credit:Alex Ellinghausen

There are 1.2 million children being cared for in childcare services in Australia. They come from 843,000 families and spend an average of 28 hours in childcare a week. And it is these 28 hours that explain why the qualifications of those caring and educating them matter and why Leyonhjelm and Hanson's ignorance really does matter.

By the time a baby is around 9 months old their brains are at their peak of being receptive to language. One of the basic things we know about how young children's brains develop is that they need interaction with a loving caregiver or caregivers. They need adults to do what is called serve and return interactions. Essentially that is a fancy way of saying that when a baby or child cries or makes noises an adult needs to respond. They need to look at the child, and speak back. When a baby tries out a new skill they need an adult to check it out with, to ask "is this OK?". This is what builds neural connections in their brains. These interactions build the very basic building blocks of the brains these baby humans will use throughout their lives.

In a perfect world families would be able to provide those serve and return interactions – they tend to do it instinctively. But our world isn't perfect and because it has mortgages and bills sometimes it makes more sense for families to go to work and leave their children in the care of other adults – childcare educators.

But you know what? Twenty-eight hours a week is a long time in the life of a baby! So we need to make sure that those million babies and children have people who have been trained about the importance of serve and return – of how to interact with those little human beings to ensure the best brain architecture gets built.