Why there can't be a general rule book for raising kids

A new review of dozens of studies involving more than 14,600 pairs of twins showed that children's genetically influenced characteristics do affect parental behaviour.

Reut Avinun of the Hebrew University of Jerusalem looked to twins, and reasoned that if parents treat identical twins, who share 100 percent of their genes, more similarly than non-identical twins, who share on average 50 percent of their genes, then it suggests that the child's genes shape parenting.

Indeed, across 32 studies of twins, they found that children's genetically-influenced characteristics do affect parental behaviour.

Researchers estimated that 23 percent of differences in parenting is due to a child's genetics. The genotype-related differences are ways that the children evoke different responses from their environment. For example, a child that is antisocial is more likely to elicit harsh discipline from parents than a more social child.

Avinun and Ariel Knafo also found that children's shared environment - socioeconomics, cultural exposure, etc. - accounts for 43 percent of parenting differences. And the non-shared environment - different schools, friends, etc. - accounts for 34 percent of the differences.

Several factors affect the extent to which genetics influence parenting. The researchers found, that age was important, supporting the argument that the child's genetic influence on parenting increases with age.

Avinun concluded, saying that parenting should not be viewed solely as a characteristic of the parent, but as something that results from both parental and child attributes. Therefore, any interventions or treatments to help parenting should consider both the parents and children, and could vary even within a family.

Because children are born differently, there never can be a general rule book for raising children, Avinun explained.

The study was published in Personality and Social Psychology Review.