I’m not an expert and have never claimed to be one. But as I read about a recent study detailing how parents are stricter with older children, I actually laughed out loud.

I’m the oldest of five girls. And I could have told the researchers that years ago. Even my baby sister’s prom night celebration is a perfect example. Last night she told my mother she was going to go bowling after the dance. My mother did not blink an eye, even when she was informed that said baby sister was then going to spend the night at her girlfriend’s house.

My prom? My mother cooked dinner for me, my boyfriend, and our double-dating friends (we had spaghetti) and then, since I was not allowed to go anywhere else, we drove straight back to my parents’ house to watch The Breakfast Club in the living room with my mother.

And no, I am not making any of that up.

So I’ll just call the recently published John Hopkins University paper vindication of my role as the guinea pig of the family. And as it turns out, my sacrifice may have actually been for the good of my younger sisters, says the study.

The study, titled Games Parents and Adolescents Play, was published in the April 2008 issue of Economic, found evidence that parents are more likely to withdraw financial support from older siblings who drop out of high school or become pregnant than from younger siblings who may find themselves in the same situation.

It was also determined that only last-born and only children are more likely to engage in risky behaviors.

Even more (and this is where my parents totally used me), researchers found that more severe discipline of older siblings was a smart move on parents’ parts, as it actually deterred younger siblings from engaging in the same acts that got their older siblings in trouble to begin with.

According to the authors’ theory, this usually works with first-born children, who recognize that their parents are going to be tougher, and as a result, keeps a cap on their rebellions. But it seems that the incentive to be strict tends to wane as the younger children reach their teen years; resulting in lost energy and motivation to follow through with threatened punishments.

My little sister could have told you that one. Wise beyond her 18 years (thanks to the four who came before her), she looked at me not too long ago and told me she knew she was lucky.

“I know you had it tough,” she said. “But I can pretty much do what I want.”

And she’s right because she can. But because my parents made such an example of how I was supposed to behave in order to set the right example for my little sisters, even I am not worried about my sister. She’s just living the teen life I had been hoping for, which included a night out with friends after the prom.