63-year-old Catherine is fed up. It is the school holidays and she has spent the whole day trying to entertain her young grandsons.

“I do everything,” she says. “Cooking, cleaning, washing – it’s pretty full-on.”

Although she loves her grandchildren very much, Catherine never imagined that she would have such a hands-on role in their lives.

“I’m getting a bit resentful now. I feel like I always have to be available to help. It’s hard work – I’m exhausted. It’s taking a toll on my health.”

Catherine is one of thousands of grandparents around Australia that have taken on regular childcare duties. In fact, according to the Australian Bureau of Statistics there are more children being looked after by their grandparents than there are in formal day-care.

The fees at private day care centres have been soaring over recent years, the average cost in Sydney is currently $100 per day. In some areas, day care centres also have long waiting lists, so having grandparents to step in and fill the gap works well for parents. But is this arrangement placing too much of a burden on retirees?

Family therapist Abi Gold says that parents need to be careful that they’re not “taking advantage” of grandparents. “Don’t rely on them to the extent that you could be damaging your relationship with them,” she advises.

It’s hard work – I’m exhausted. It’s taking a toll on my health

“I have had a lot of clients who criticise their mothers or mothers in laws for putting their own social engagements ahead of looking after the grandkids. But that’s just not fair – you can’t expect the grandparents to always be on standby.”

Gold also notes that family rifts can develop when resentment builds up. To avoid this happening Gold advices grandparents to be honest and up front about how they are feeling.

“It’s important to keep the lines of communication open. Grandparents need to do what is right for them, not what is right for their children,” Gold explains.

In some cases this may be easier said than done – 55-year-old Trish was enjoying a “new life” with her second husband when her 18 year-old daughter fell pregnant.

“My daughter is still at school, so she can’t afford to pay for childcare. I am happy to have the baby, he is gorgeous, but I don’t like the fact that she thinks it is a given and it is my job,” says Trish.

“I resent having to adjust my new life to babysit, when my new life has only just started. But there really isn’t an alternative at the moment.”

For some grandparents though, helping out with childcare is just the “natural” thing to do. 57 year-old Alan lives with his daughter and son in law and “loves” to help out with his granddaughter Talie.

While Alan acknowledges that it can be “hard work”, he says that it also makes him feel useful. “It gives the parents a break and that’s great.”

“I have story time with Talie every evening, we tell stories and play together,” says Alan. “I love it.”

* Names have been changed