Poor parenting is fuelling a rise in the number of young children who grow up with behaviour and educational problems, according to new research.
Researchers found that as many as four-in-10 infants fail to properly bond with their mothers and fathers by the age of three --- storing up a series of social problems in later life.
The study, commissioned by the Sutton Trust, found that strong emotional bonds between parents and children were vital to ensure youngsters develop properly in the first few years.
Parents need to reassure sons and daughters with smiles and soothing tones while acknowledging their unhappiness when they get upset to lay the foundations of children's social skills.
But the study --- carried out by academics from British and US universities --- found that 40 percent of children failed to develop these bonds because of poor parenting, increasing the likelihood of being badly behaved and underachieving at school.
Researchers warned that the issues applied to "families from all social classes", adding that boys' behavior was more easily affected than girls' by poor parenting.
Children without secure bonds were more likely to display behavior problems, including aggression, defiance and hyperactivity when they get older, the study found.