Research from the Resolution Foundation showed that one in three millennials is unlikely to ever buy their own home. The number of young adults living at home has also reached all-time highs – the latest figures from 2017 suggest 26% of people aged 20 to 34 are still living with their parents.

Some parents may feel their adult children have enough on their plates as wages fell behind inflation, but research from the OneFamily Intergenerational Lending report shows that children cost their parents an average of £260 per child per month. It also showed that 55% of adult children — around 2.4 million — do make a contribution to their board and lodging.

In calculating the right amount, you need to look at the additional expenses associated with having them at home – extra food, fuel, telephone/internet. Then you need to decide on an appropriate contribution to household expenses. More and more people still have a mortgage in later life and there will always be bills such as council tax.

Another question is what they would be paying elsewhere. Anywhere in London is going to cost around £100 a week for a shared house, and it’s unlikely anyone would be doing their washing or making sure there was a pie in the fridge for their dinner. Some parents may feel that children should get a realistic notion of the cost of running a house.

There is also the question of what you do with the money once you’ve got it. Kinder parents will save up the rent from their children with the aim of gifting it as a deposit on a home later on. Others may feel they’ve deserved a break and will spend it on improving their lifestyle.

A quick survey of Mumsnet users suggests the going rate is around £50 a week, with the key difference whether you would secretly rather they left, or secretly rather they stayed.