A new study has revealed that eldest children are more likely to be punished by their parents for breaking the family discipline.
Ginger Zhe Jin, an assistant professor of economics at Maryland University in the US who co-wrote the study report, revealed that first-born children were meted out harsher punishments by their mothers and fathers.
The study also showed first-born children to be more likely to suffer financial penalties, such as stoppage of their pocket money .
According to the researchers, parents usually grow tires of the so-called tough love by the time younger children are born.
In their study report, appearing in the Economic Journal, they write that younger children run a greater chance of going off the rails when they grow up.
Drop out of school, drink, take drugs or become teenage parents are some of the risks that younger children face, says the report.
The researchers believe that their study will raise fresh questions about the way some parents raise their children.
"Tender-hearted parents find it harder and harder to engage in 'tough love' since, as they have fewer young children in the house, they have less incentive to uphold reputations as disciplinarians," Zhe Jin wrote in the report.
"As a result, the theory predicts that last-born and only children, knowing that they can get away with much more than their older brothers and sisters, are, on average, more likely to engage in risky behaviour," Zhe Jin added.
The team of academics studied data from the US Bureau of Labour Statistics to determine how children born at different times turned out.
They observed that first-born children were generally better-behaved and less likely to get into serious trouble in their teenage years.
The team further observed that second or third-born children were also more skilled at "playing the system" after seeing how their older siblings were treated by their parents.