Experteye: Oliver James

The earlier a dad leaves, the younger the daughter starts sex

Results from two large US and New Zealand samples found that one-quarter to one-third of girls whose fathers separate or divorce from their mothers before they are aged six have a teenage pregnancy. This was seven times as many as girls from intact homes. Girls from early broken homes were two to three times more likely to have intercourse before the age of 16. The earlier the father left, the greater the likelihood of early sex.

Even when other factors, such as low income or lack of education were taken into account, paternal absence remained the crucial determinant of how young sex started and of pregnancy rates. This could be because girls from broken homes learn dating habits from their mothers. It may also be that they are using nubility to get the love missing from their father from other men.

Implication: if you are a single mum, don't flaunt your new dates, and encourage bonding of your daughter with her father.

Child Development, Vol 74, 3, 801-21 (www.blackwell-synergy.com).

Why kids of working mums may get stir crazy in the afternoon

A definitive US study shows that levels of cortisol, the "fight or flight" hormone, which prepares us to react to stressors, was raised in the afternoons among infants and toddlers with working mums. This was not so on days when these children were cared for by their mothers or with children cared for full-time by their mothers. It may explain why some children seem"high" or aggressive after day care. Since heightened cortisol impairs the immune system, this may explain why children in day care are at greater risk of illnesses.

Implication: researchers recommend that minders reduce competitive activities in the afternoon, and encourage quiet play towards the end of the day.

Child Development, Vol 74, 4, pp 1006-20 (www.blackwell-synergy.com).

Loving mum, good kiddy

Mothers who are warm and consistent disciplinarians have toddlers who are more likely to be well behaved with their minders. How warm or consistent the minder is does not predict how the child will be with the mum.

Implication: if you are a minder who wants an easy life, try to find children with warm and consistent mums.

Developmental Psychology, Vol 39, 4, pp 680-92 (www.apa.org/journals).

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Thanks to guardian.co.uk who have provided this article. View the original here.