Get some perspective. In some cultures, they actually are. This could be for many reasons:
* The girl will marry and join another family, leaving no one to care for the parents in their old age.
* Because of traditional gender roles as well as physical attributes, the girl won't be able to toil the fields (doing so might make it harder for her to find a good husband). A child that can do so is more valuable.
* Only sons can inherit land
* Only sons can carry on the family name
That was actually the reality in most places of the world for most of human history, and unfortunate as it is, still the reality in some cultures and countries. It isn't bullshit.
Assuming that you don't buy into that bullshit, could you then please explain why the gender imbalance is currently at 1.16 to 1, when naturally you would have slightly more women than men? Because it sure seems like the Chinese believe they have a reason for preferring boys.
Only if you actually buy into the bullshit that girls are worth less than boys...