How did the dowry contribute to female children being less desirable than male children?

The father (or family) provided a dowry to the gentleman that married their daughter. The "husband" was then responsible for said daughter. This was important in the past since women couldn't own land, or even work in most careers. The male children in any family we're important not only for labor, or to earn money but also to ensure the family name carried on. However I'm quiet sure you knew all that and are only on here to mess with people