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If you’re a firstborn child you already know you’re probably smarter than your younger siblings but is that true? Well apparently, it might be. 

According to research published in 2016 in the Journal of human resources, firstborn children do tend to outperform their younger siblings overall. This meaning they normally end up getting higher scores on cognitive tests and things of that nature. This happens because it seems parents try harder with their firstborn kids than they do with the rest. 

The abstract of this specific study goes as follows:

We document birth order differences in cognitive and non-cognitive outcomes and maternal behavior from birth to adolescence using data from the Children of the NLSY79. As early as age one, latter-born children score lower on cognitive assessments than their siblings, and the birth order gap in cognitive assessment increases until the time of school entry and remains statistically significant thereafter. Mothers take more risks during pregnancy and are less likely to breastfeed and to provide cognitive stimulation for latter-born children. Variations in parental behavior can explain most of the differences in cognitive abilities before school entry. Our findings suggest that broad shifts in parental behavior from first to latter-born children is a plausible explanation for the observed birth order differences in education and labor market outcomes.

For this study researchers from the University of Edinburgh, the Analysis Group and the University of Sydney used data from the US Children of the National Longitudinal Survey of Youth who were monitored from pre-birth until the age of 14. These children underwent assessments every 2 years as data was being collected.

The University of Edinburgh wrote as follows on these findings:

Researchers applied statistical methods to economic data to analyze how the parental behavior of the child was related to their test scores. 

The researchers then used an assessment tool, the Home Observation Measurement of the Environment, to observe parental behavior, including pre-birth behavior, such as, smoking and drinking activity during pregnancy, and post-birth behavior, such as mental stimulation and emotional support. 

The findings showed that advantages enjoyed by firstborn siblings start very early in life – from just after birth to three years of age. 

The differences increased slightly with age and showed up in test scores that measured verbal, reading, math, and comprehension abilities.

Researchers found that parents changed their behavior as subsequent children were born. They offered less mental stimulation to younger siblings also took part in fewer activities such as reading with the child, crafts, and playing musical instruments.

Mothers also took higher risks during the pregnancy of latter-born children, such as increased smoking.

How do you feel about all of this? I, for one, think it makes a lot of sense, even though there are of course exceptions to this. Were you a firstborn, and are you the smartest of your siblings? For more information on this, take a look at the video below.