When it comes to kids, first is always the best. Here's why

There’s a reason your first-born child is the way he is.

The oldest in the family gets the best of a parents’ child-raising abilities, says a new study of parent evaluations of their children from the National Longitudinal Survey of Youth in 1979. According to The Atlantic, which breaks down the study, first-borns have higher IQs, do better in school and are more likely to be rated as above average by their parents.

You might think that parenting gets better with practice but sorry, subsequent kids: Science says you get the parenting dregs. School performance declines the farther down you are in the birth order, as does consistent parental discipline. (But you knew that already.)

The study lays out the various theories as to why number 1 kids are well, number 1:

• Parents don’t have to divvy up their time with just one kid, diluting their attention
• Some think the quality of genetic material diminishes with each birth
• Younger kids have no little sibs to teach, which is linked to better learning
• Mums and dads just get lazy with kid number 2 because children suck your will to live
• Parents might stop having kids once they have their “problem child,” so the poorer performance of younger kids reflects selection bias
• First-borns are less likely to have their early schooling interrupted by divorce

The researchers also speculate that mums and dads engage in strategic parenting, where they establish more rules with the first child so their strict rep trickles down to younger kids. Interesting theory, but was the way you raised your first child all part of a diabolical plan? We have enough problem coming up with what to make for dinner, much less hatch a plan for getting our theoretical future children to fall in line.

Mom of two Sasha Emmons is a writer and editor. Follow her on Twitter and Google+.