Throughout our history, parents have preferred boys to girls. When boys carried on the family name and ensured the continuation of the family line, they were the key to a family's success and happiness. But for the past 50 years, our male preference has stayed relatively the same. It's the 21st century, American moms and dads are still hoping their little ones will be boys, by a 40 percent to 28 percent margin.

We think boys are easier. With boys, they say, you don't get all the drama that comes with girls. You don't have to deal with petty fighting, hormonal imbalances, and the ups and downs of girl life. You don't have to worry about her teenage years, when she fights to dress a certain way and starts dating boys.

How does this anti-girl rhetoric affect our expectations as parents? And what exactly does it say about our girls?

Pregnant with her third daughter, a mother I know routinely endures comments from people who insist boys would be so much easier. They reassure her that maybe next time, she'll have that long-awaited boy. But she and her husband like having girls, and they don't want their daughters to think that somehow a boy would have been the more preferable option.

There's nothing wrong with dads dreaming of a son to play sports with, teach the tools of his trade to, and carry on his family name. I hope to have a daughter some day for the same sort of reasons.

Our seemingly lighthearted comments about the "ease" of sons and the "difficulty" of daughters, though, are steeped in a troubling worldview.

LZ Granderson wrote for CNN that he hadn't even left the hospital with his new bundle of joy before a nurse told him how blessed he was to have a son rather than a daughter. Granderson said:

At the core of this line of thinking isn't safety – it's sex. When someone offers this piece of advice, it's with the thinking that girls have to be protected from boys who will say and do just about anything to get in their pants. What's typically missing from this discussion is the challenge to parents – particularly fathers – not to raise a liar and a cheat.

True, parents of boys do not have to worry about them coming home pregnant, but does that mean an unplanned pregnancy can be considered "the girl's problem"? After all, a boy's girlfriend did not get pregnant asexually. That's why I'm Tebowing day and night, hoping my 15-year-old has the will to stay away from sex – even though the world all around him tells him there's something wrong with him if he does.

This prevailing line of thinking presents the world, to parents and their children, as one big scary place filled with hormonal boys and men waiting to take advantage of girls.

Our preference for boys over girls perpetuates a double standard regarding sexual behavior namely that boys can be "boys" while girls need to be pure.

While parents may have a myriad of reasons for preferring boys, these underlying perceptions play a factor. As Granderson wrote, "This kind of thinking is handed down from generation to generation almost as soon as the umbilical cord is cut."

In societies where female infanticide is high, we also a see a skewed understanding of male and female sexuality. It may be hard for us to believe that in some parts of the world today, being born female is pretty much a death sentence. We can barely imagine how, in places like India, ultrasound technology is restricted to avoid revealing results the mother and father aren't pleased with. Christians have rallied against sex-selective abortions in our own country and worldwide, but Americans still experience our own disparities in welcoming boys and girls.

When our daughters hear us (and they do hear us) say that boys are easier, even if it is in a joking manner, we are perpetuating the sinister belief that girls have less value than boys. As Christians, we believe that boys and girls equally bear the image of God and are equally worthy of life in this world. God created us male and female for a reason, and each gender is necessary for the continuation of this society and to reflect his glory.

Parenting is hard work. There is no doubt about that. Parenting is hard work not because of the gender of our children, but because sin entered the world shortly after God declared men and women equal in his image. Boys are difficult to raise and girls are difficult to raise because even in their cutest and most precious moments they are still sinful human beings in need of a Savior.

As Christians, our daughters need to hear from us that they are valued and wanted from the moment we hear the ultrasound tech say, "It's a girl," because in God's economy those are beautiful words.