The value of respectful conversation
But it is later on, during primary and secondary schooling and then working life, that it is paid off.
"The value of respectful conversation and communication cannot be underestimated," she says.
"It is about their future employability, their ability to communicate well, the building of resilience and the ability to appropriately convey information – even if that information is negative."
Professor Pendergast says the knowledge base that comes with a child's exposure to robust and respectful conversation is self-evident.
What isn't as obvious, however, are the emotional and social benefits.
"If your child is effectively engaged in conversation from an early age, they grow to be someone who can adapt and be resilient enough to communicate with someone who is unexpected or be able to meet someone unknown.
"The cognitive experience alone is beneficial."
Speaking in full sentences and engaging children in "adult" conversations is something long-time librarian, mum and classroom volunteer Claire Grandcourt is passionate about.
Engaging your child in real conversations
Claire, who has worked in public libraries for more than 20 years, says there is a clear divide between the children who are engaged in real conversations and those who are not.
She says especially with the flood of hand-held devices into family life during the past decade, the need for good conversation at home is paramount.
"If a child cannot communicate it leads to frustrations and it can also affect behaviours," she says.
"If a child isn't engaged in conversation with a parent, or if a parent doesn't speak to their children in clear, complete sentences, then the child will lose interest in that. It's just like if a parent doesn't engage in play with their child.”
Now a little common sense: by adult conversation, we're saying full sentences and a sensible, engaging and accessible tone. Content censoring is always important.
Both professionals maintain good conversation opens the lines of communication. Children can articulate their needs, but also have the means of seeking explanation or questioning someone in a respectful but confident manner when something doesn't make sense.
Claire takes a step back though, to something far more fundamental.
"If parents don't speak with their child as an equal, they are limiting their ability to really know their child's interests and what's going on with them," she says.
"They cannot be fully involved with their child and what they like or don't like; what interests them, what their fears or concerns are, what their favourite things are.
"We do see a lot of disengagement with children. Parents are undoubtedly busy. But there are always distractions and often it's the device we carry around in our hand.
Making the most of support services
Claire says while it could be tricky for parents to engage in conversation with their children, there was an abundance of support and great services. The key was knowing where to look.
Libraries, child health nursing centres, your GP, paediatricians and speech therapists and pathologists were great places to start.
"We have identified that while there is a great deal of support for parents and children from birth to about six weeks of age, and then through to the age of one, there is a big gap between the ages of one and then four, when four-year-old immunisation is due.
"So, there have been a number of programs and a lot of information produced to help bridge that gap. This will give parents support, but it also means that issues which might not be picked up until kindy or early primary school, are more likely to be identified sooner."
Services will vary from region to region throughout the country, but the public library and your GP is a good starting point.
In the end, it all comes down to this:
"A child's ability to communicate comes from their parents," Claire says.
"We don't want to guilt mothers (or fathers), or judge. We know they have enough of that as it is.
"But we do need to encourage all parents to engage. Speak to your children in full sentences. Don't use baby talk and encourage the correct use of words and phrases."
Both experts assert that it's not just about the here and now, the developmental milestones and a well-developing child. It's about setting them up for the future.