Having grown-up children living at home could cost you dearly in terms of your planning for retirement, according to a study.

The recent recession and the ever-growing gulf between house prices and salaries means that adult children are increasingly having to stay with mum and dad while they save up a deposit.

And a survey by peer to peer lender Zopa puts the cost of that at an average of £32,664 and that four in ten parents face pushing back their retirement a further three years just to support their children.

Typical things which parents usually find they have to stump up for include weddings, a first car and university fees.  The research also found that girls are more expensive to accommodate than boys. Daughters cost their parents an average of £35,920, while sons cost them around £30,251.  

Nearly two in three parents have dipped into their savings, and seven in ten said they have adjusted their lifestyle to cater for the extra costs.