THE stagnation in social mobility has been caused by bad parenting in working-class families, where the adults fail to instil self-discipline in their children, a study has found.

The research by Demos, the left-leaning think tank, finds that the richest in society are nearly three times as likely as the poorest to foster the character traits necessary for a person to get on in life.

The study reveals the gulf has widened because of the absence of “tough love” upbringing in too many working-class households.

This has been exacerbated by the collapse of marriage among the poorest families — the children of married parents are twice as likely as those from single parents to have the most important characteristics for success.

The findings by Demos challenge Labour thinking. Ministers often blame elitism in the professions and the education system for holding back the children of the poorest families.

Jen Lexmond, co-author of the Demos report, said: “Poor children are doubly disadvantaged. Not only are they economically disadvantaged but their character development is also hindered by lack of parenting skills. Their parents struggle to set limits and stick to them.”

The Demos report, called Building Character, finds that social mobility — children doing better economically than their parents relative to the rest of society — rose from the second world war to the 1970s and then stagnated, although it might have improved a little since 2000.

By analysing detailed studies of more than 10,000 households carried out since 1958, Lexmond and her team identified three traits that are the most important for a child’s chances of improving their economic lot.

These are application, defined as the ability to concentrate and stick with tasks; self-regulation, whether someone can control emotions and bounce back from disappointment; and empathy, the ability to be sensitive to other people.

The type of parenting most likely to inculcate these characteristics is defined as “tough love”, in which children are given clear rules and boundaries, instilled by discussion and affection. This type of parenting is more common in the wealthiest families.

Researchers found that children who could hold off eating a marshmallow — with the promise of getting two later if they succeeded — did better at school and better in later life.

The Demos researchers say children living with both biological parents are twice as likely to develop the most useful character traits as those living with lone parents or a step-parent.

In families where parents are disengaged, children are three times more likely to develop negative characteristics. In the most extreme cases, the researchers found children could become emotionally insensitive or “callous”.

The report states: “Callous children grow up lacking a sense of empathy and guilt, and learn to see others in a purely instrumental way. [There is] a level of disengagement in a small minority of parents that would be considered neglectful.”

The researchers found that children in low-income families where their parents adopted a “tough love” parenting style were just as likely to develop positive characteristics as those in richer families.

Michelle Mone, 38, grew up in the east end of Glasgow and left school at 15. In 1996 she set up MJM International, which produces the Ultimo range of lingerie.

She said: “My mum and dad bought me up with respect and taught me that you have to work. They drummed that ethic into me.

“I think that’s what’s missing today. Today teachers have absolutely no power. We’re losing everything that we used to have.”

Lexmond said more money should be directed towards helping families while children are still young. She suggests expanding the role of health visitors to encourage supportive parenting.

Lexmond said: “The foundations for our children are laid before the age of five. This puts a huge responsibility on parents. But when it comes to parenting, it is not what you are, but what you do that’s important.

“Parents on a low income, but who are confident and able, are as effective at generating character capabilities in their children as parents on a high income.”

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