New research carried out by the University of Edinburgh economists has found that first born children are likely to be more intelligent than others that come after.
The researchers, collaborating with a team from from Sydney University, examined data from 5,000 children who were given reading and picture vocabulary tests every two years.
They found that first-borns generally achieved higher IQ test scores from as young as one year old.
By analysing the results in relation to parental behaviour, they found first-borns were given more support with tasks that involve thinking, and subsequently scored better on the tests.
The study, published in the Journal of Human Resources, looked at children’s mental progress from pre-birth to age 14 and found the difference in test scores increased slightly with age.
All children were found to receive the same level of emotional support, but parents appeared to spend less time on brain-stimulating activities with their younger children, took part in fewer activities with them such as reading, crafts and music.
Essentially the study found that parental behaviour with the kids change as first-borns apparently get given more support when young and aided with more guidance in thinking than subsequent kids. Thus the first kid grows up to perform better in tests and life apparently.
The University of Edinburgh and Sydney University study used data collected by the US Bureau of Labour Statistics, but experts have warned any results are generalities, which may or may not translate to individual families.