A new research reveals that parents do not offer the same mental support to all of their children.

Firstborn children are smarter, according to study

The study is conducted by a team of scientists from Analysis Group, University of Sydney and University of Edinburgh - collecting data of firstborn children from U.S Children of the National Longitudinal Survey of Youth.

Researchers studied almost 5,000 children (before birth until 14 years old) in the United States. Once every two years, the children must undergo a set of cognitive and reading tests with supporting data including family background and their financial conditions.

The research analyzed closely how parents treated and devoted their time for all of their children. However, the mental stimulation wasn't equally given. The simulations, according to author Jee-Yeon Lehmann, Ph.D., were in forms of reading activity, family outings or DIY craft-making.

Beyonce, Taylor Swift, and Adele are the famous examples of firstborn children. Bill Clinton, J.K. Rowling and Kate Middleton are also the oldest children in the family

Personality, behavior, and intelligence

It makes sense if the firstborn children are tied to better personality and intelligence. For instance, the first child may get more attentions from parents, according to Forbes. And parents may also teach their firstborn how to be reliable, caring, discipline and responsible for their younger siblings.

These attentions could result in better cognitive skills which translate to a more established individual.

Are middle children less smart?

Being squeezed by the first and last born children make the middle kids a peacemaker in the family.

In a separate study, however, scientists have found that firstborn children may be prone to numerous health issues such as obesity and food allergies, Health reported.

Regardless of the studies, Lehmann added that the difference is insignificant and the study is done to motivate parents to spend more time doing activities together with their children and be alert on the importance of early development.