Children with older sisters in developing countries do better, study suggests

Having an older sister can have as much of an impact on a child's development in low- and middle-income countries as whether their mother finished secondary school, a new study has suggested.

Using data from an early literacy intervention programme in western Kenya, the study from the US Center for Global Development (CGD) found that young children with an older sister, as opposed to an older brother, performed better on an age-adjusted early childhood development index.

The difference - about 0.12 standard deviations higher on the index - was around the same as between children whose mothers completed secondary school and those whose mothers completed primary school.

There was an impact on both vocabulary and fine motor skills, the researchers said.

The paper, Big Sisters, suggested that the difference may be because in many cultures, particularly in rural areas and among subsistence farmers, older sisters take on childcare responsibilities while parents work in a way that older brothers are not expected to.

They also found that older sisters engage their younger siblings in stimulating activities, often even more than the parents themselves.

"It appears that these stimulating activities have an impact on young children’s development," the study says, although with the caveat that the research covers just one region.

Pamela Jakiela, fellow at CGD and author of the paper, said other researchers had dismissed the findings as "anthro 101" - in other words, blindingly obvious - but that missed the point of the research, which highlighted the impact in order to assess whether policies and resources aimed at helping children reach their potential were being directed in the wrong place.

She said that it was hard to leave behind the "OECD lens" of richer countries, where the focus is on the parent making the investment into the child's development, meaning that the role and impact of older sisters in other settings is often ignored.

Many measures of early childhood stimulation, including questionnaires used by Unicef, capture how much input 3 and 4-year-olds have from parents in terms of things like reading or singing, but do not touch on their older siblings at all, she said.

However, she warned that, for the older sister, spending more time looking after their younger siblings probably meant that they lost out on their own opportunities for schoolwork and play.

"We don't want to emphasise this to validate it, to legitimise sticking extra work on girls," said Ms Jakiela, stressing that the hope was that in the long-term, girls would have to play less of a role in childcare.

But for now, she added, "trying to design policy with blinders on about the reality of how work gets done is not a good way to go forward."

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