Sons cost their parents almost €23,000 more than daughters, according to a new UK study.
The study, carried out by pension-advice firm Portafina, claims it is because boys tend to live at home longer, until they are 26, whereas girls fly the nest at the average age of 22.
The four-year difference adds up to a €23,000 bill for parents.
Meanwhile, 20% of parents refuse to take any money from their children to help pay the bills.
These adult children who live at home think that if you're working and still under your parents' roof, you should be handing up.
"Before I started saving for my house, I did have to hand up rent, but my parents then, when I did start to save for a deposit, were really sound and said 'look, put your rent you are going to give us into putting it away'.
One was adamant that parents should expect something from their adult children.
He said: "I always do try to contribute as much as I can, but I do feel that they should expect it."
Another said: "It depends on what the person is working at, if they are earning a good wage, then I think it's a nice thing to do."
Some parents said they even dipped into their pension pot or worked extra hours to help pay for bills racked up by their adult children.
The average adult child living at home costs parents €470 per month for food, bills and handouts.