The swelling ranks of boomerang kids, who return to their parents’ home in adulthood and remain there into their 20s or even 30s, are putting enormous strain on family relations, according to a leading charity.

Young adults still living with their parents are frequently said to be suffering from “failure to launch” syndrome, characterised by an inability to see what the problem is.

It is not just that they treat the family home like a (free) hotel, it is also that many of them refuse to accept that their lifestyles clash horribly with their parents.

The results can mean extra money worries and stress for parents and, at worst, physical and verbal aggression from their children, often fuelled by alcohol and drug abuse.

The charity Parentline Plus is now so concerned about the number of calls it is receiving on this issue that it is drawing up a self-help guide for parents in this position.

One caller told the charity’s free, 24-hour helpline: “I’m not sure what my role is with my son now. As a mother I feel very insecure at this point. This is a transition and difficult for me as a parent to adjust to this new relationship.”

Another said: “Our home became a war ground of constant arguments about alcohol misuse, bad language and lack of respect for us and our home by our son.”

In a report entitled Will They Ever Fly The Nest?, the charity calls for more support for parents of young adults to assert what authority they have, especially where adult children are violent or misuse drugs.

Dorit Braun, the charity’s chief executive, said there was an assumption built into government policy and social norms that young people magically became trouble-free and responsible as soon as they reached adulthood. The reality could not be more different.

“Living with young adults is as perplexing and concerning as any other stage in a parent’s journey, yet parenting strategies seem to end with adulthood, as though once children become adults, parents are off the hook,” she said.

Ms Braun urged the Government to find ways of supporting parents of young adults to influence their children’s work and personal choices. Parents also need more information about issues such as housing benefits, grants and training, she said.

A survey of 575 calls to the charity’s helpline found that nearly 10 per cent concerned this issue.

Nearly 70 per cent of callers worried about regular use of category C drugs. Problems were particularly acute where children had left home, possibly to study away from home or set up house with a partner or friend, only to return. Once they had had a taste of freedom they were more likely to treat home “like a hotel”.

Some parents despaired that children would not leave home until their late 20s. Many found it hard to persuade their children to look for work.

Student debt, the housing shortage and a general lengthening of adolescence (itself a result of growing life expectancy), are all contributing to the well-documented phenomenon of boomerang kids.

According to government figures, the proportion of men in their 20s living in the parental home has grown from 59 to 80 per cent in the past 15 years. Among women, the rise has been from 41 to 50 per cent. Over the same period, the median age of first marriage has risen from 26 to 30 for men and from 24 to 28 for women.

Suzie Hayman, a counsellor for the charity, said that although it could be a joy for parents to share their house with their adult children, the potential downsides were huge.

“By the time parents ring us, really serious issues have emerged,” she said.

It’s your house – and your rules

— Insist on a contract stipulating a financial contribution
— Draw up an agreement on chores and house rules, then stick to it
— Do not wait upon them hand and foot
— Do not treat them like teenagers and do not try to control them
— Accept that you have to go through a transition in behaviour with adult children
— Ensure that both parents are on the same side. If a father expects the mother to do all the chores, the adult child will too
— If behaviour upsets you, speak to them
— Insist that they tell you if they are not coming home at night
— Be prepared to say: “I love you, but not your behaviour”
— Remind them that this is your house. If they do not like your rules, they must leave

Source: Parentline Plus

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