Thank you, to a silent army of grandparents.

There is a silent army that today, we wish to thank. A band of tireless workers who never get enough recognition. A legion of loving, caring, unpaid carers who step up each and every school holidays to fill in the gaps.

Grandparents.

Right around the country these school holidays, grandparents are sacrificing their own time and money to hold the fort while parents grapple with working hours that do not equate with school holiday hours.

You see them waiting at the bus stop shouldering backpacks filled with Tupperware boxes of cut-up fruit and cheese. You see them pushing prams with younger siblings gazing out as they make their way out for the day. You see them queuing up in the lines to museums and play centres. You see them pushing the swings in parks. You see them watching a game of tag on the beach.

You never see them complain. You never hear a bad word. Not a gripe or a grumble. They just do as they are asked.

Many of these grandparents never thought for a second their retirement would be filled with hearing about Mincecraft and My Little Pony. They envisaged travel, gardening and long languid days immersed in all those books they never got to read when they were in the trenches of parenthood.

And then their grandchildren arrived.

Tiny downy-haired creatures that captured their hearts and turned their lives upside down. They never believed they would feel this way again. As the years passed by did they ever realise what they were in for? How much they would be needed?

What we so often fail to tell them though is just how they are appreciated.

Oh we thank them, as we rush in from work and are assaulted by the sounds and smells of family. All in a hurry we hear tales of outings and squabbles and find ourselves drenched with kisses and love. It’s hard at these times to turn to the ones who have cared for them all day and exchange much more than a round-up of the day’s duties - a simple thank you is often neglected, even thought we feel it.

A recent study has shown just how many of our parents' generation are caring for their own grandchildren as an informal method of childcare. A study by the University of NSW and reported by Fairfax Media, found that three-quarters of grandparents believe regular childcare is a normal part of their role.

The study found that most enjoy it, but that providing more than 13 hours a week was a tipping point – one that they found difficult to juggle.

WATCH the video for the reality of grandparents caring for our kids. Post continues after video..

It is such a common sight that we take it for granted. According to the Bureau of Statistics, grandparents are the most popular form of childcare in Australia with 837,000 children looked after by their each week by their grandparents.

The research found that 70 per cent of grandparents had changed the days they worked. 55 per cent had actually cut back the hours they worked and that childcare responsibilities take precedence over work for half of all grandparents.

At each and every turn these school holidays I have seen them. The elderly man playing hide and seek with two rusty-haired twins in the park. The elegant silver haired woman treating her granddaughters to a milkshake listening intently to their every word.

The youngish looking women, too young I think to really be grandmas, gossiping about the world over the wooden fence while their dark-haired grandson and a wobbly-legged girl scoop up mud in their pudgy fingers for home-made mud pies baked on the asphalt driveway.

The Nona laden down with nappy bags at the supermarket, struggling to unfold an space-ship looking stroller complete with more gadgets than her phone.

We see their devotion and smiles when they arrive to pick our children up and we try to brush aside their tired expressions when we relieve them of their duties at night.

Do they realise that we know how much we owe them? How safe and secure we feel with our precious children left in their care. Do they realise how aware we are that our children have changed the course of their lives? That travel and adventure was placed on a back burner for us so that we could get on with our careers, so that we could forge a way for our families?

For those who step up each and every holidays, each and every time we have to work and our baby is sick, each and every time an unexpected meeting crops up or an unforeseen delay sees us needing them, we say thank you.

Do you think they know how grateful we really are? Let's tell them.

What do your children's grandparents do for your kids?