One in five Australian school kids is starting school "developmentally vulnerable" in at least one area such as language, cognitive skills or communication, new research shows.
It also found a major factor in determining a child's "preparedness" for school is socio-economic background as well as language ability, particularly among families who speak a language other than English at home.
"It creates a big gap between the top and bottom. There's a group of kids at the top end coming very well prepared, and a group at the bottom coming less well prepared," said UNSW Professor Trevor Cairney, who researches early childhood education.
For parents, it means teaching children basic literacy skills through reading to them from a young age. If the habit was missing, Professor Cairney said, it could have adverse effects well into the future.
"If [disadvantaged children] go into year one, the gap simply widens. We've known for many, many decades that if there's an achievement gap between children without significant early intervention, that the gap will grow," he said.
Previous research conducted by the University of Queensland has clearly shown that the single most important determinant for a child's success at school is how much they are exposed to reading from a young age.
"Part of the equation is reading to children, part is improved early learning education in low socio-economic areas, and part of it is schools being more prepared. Kids that come from wealthy families are more likely to be being read to."
For Sydney mother of three Rebecca Armodoros, reading each night before bed has been an important routine for her entire family in her St Marys home. Her son Noah, 4, will soon begin school himself.
"We do try to do it every day. I suppose it's one of his necessities," she said.
"The great thing is sometimes if I'm not able to read the story, his brother or sister are quite happy to read the story with him."
Kevin Robbie, CEO of United Way, an Australian charity that runs early literacy programs within disadvantaged communities, said many young parents simply aren't aware their child's learning starts before they enter the classroom.
"Rather than just being the school's responsibility in teaching the child to read, it's also parents'," he said.
"It's a whole-of-community issue. You can look at government and schools and curricula, there'll always be a role there. But for us there's a business imperative and a family and community answer that's needed."
Mr Robbie said that despite increasingly busy lives for working parents, there will always be a need for time spent reading with young children.
"You end up running around chasing your tail half the time, and you have to care about that time to make reading important."