The empty nests have begun filling again, as young adults who had flown the coop come home to roost, at least until they have saved enough to buy their own coop.
This housing crisis phenomenon means that all over the State grown-up kids are arriving on Mum and Dad's doorstep with their pot plants and duvets.
There is increasing pressure on first-time buyers to have large cash deposits. They have to stretch their financial capabilities to get a mortgage big enough to cover most of the cost of any house, anywhere.
With rents now almost as high as a mortgage, its more difficult - some would say impossible - to save while renting. Many young people are resorting, in their frustration, to moving back to their childhood bedrooms. But their parents may have been getting ready to make that room into a study.
"It thwarts the normal life cycle and expectations, of the predetermined pattern of marriage, children, and then retirement once the children have left," according to Ms Marie Murray, director of psychology at St Vincent's Psychiatric Hospital in Fairview.
"Couples are at this stage looking forward to being able to enjoy each other and spend time on their own, with whatever retirement packages they have, while they're still young and energetic enough to be able to enjoy it. The problem is, it's happening at a time when couples may have made more significant plans together, like a reward for the years of work and rearing the family."
She says it can be a positive experience and generally parents are very supportive of their children's plans. "Parents invest so much in their kids and they really want to help them to get their own place and are glad for them." However, she warns that unforeseen issues will challenge even the most enthusiastic parent.
"A lot of things have to be negotiated. Music, watching TV, having friends around, family meals and who cleans up after them. It's on the apparent trivia that these things can founder."
Apart from the practical benefit to the child of saving money, there can often be a more intangible benefit in the new relationship between parent and child. "It can allow parents an opportunity to really get to know their children as young adults.
"They can watch the success for themselves as parents, to see these young people trying to achieve something and being prepared to make a sacrifice."
There can also be other, more practical, advantages for the parents, who now have someone to mind the house while they enjoy their weekend breaks and foreign trips with nothing to worry about. For widows and widowers there is the boon of permanent companionship and security, particularly at night.
The biggest dangers arise, Ms Murray explains, if no plan is laid out in advance for the time when the younger adult will have achieved his or her target and move out. "If there's no structure then it might seem to be just free accommodation, or where the child is spending excessively and living a lifestyle inconsistent with the declared wish to be saving. Though, of course, the child will say they have to have some life, and they're right.
"Discussing and planning it properly are essential. Setting a time limit on it, and above all respect on both sides for the life stage that the other is at, will avoid a lot of problems.
"At the end of the day, parents have a wonderful opportunity to do something really important for their children."