Daughters move out of their parents home at age 10

[kcchung]

Trying to learn more about a new story I heard today. 

My MIL told me in her village in Xinhui area, once the daughters reached the age of 10 they had to find another place to sleep.  Part of the reason was their houses were too small and could not house them - This was before the 1 child rule.

They would still work with their parents in the fields and eat with their family.  They wouldn't sleep at their home anymore.

Single or older women would house these young girls.  In my MIL village they would collect the added girl's waste (feces and urine) to sell to the farmers for fertilizer.  This would only be for a few years because most girls married about 14-15.

I am curious if anyone could shed more light on this subject.  Was this strictly a point of their parent's house was too small or was there something going on here?

[genekl]

My mother, an unwanted third daughter, was adopted (sold) about age 9. She says it was a real blessing from God that she was married off (sold again?) to an American G.I. and taken to heavenly USA!

Jason Wu in another thread here said, which largely was my mother's experience: 

To address the question of adoptive daughters; I am not quite sure if the monetary exchange would be the same but I would believe that adoptive daughters would cost less since they are of no use in terms of succession and ancestral worship. In harsh reality, girls would often be bought as servants rather than daughters. For example, my maternal great-grandmother purchased two young girls from two impoverished families who could not afford to support all their children, however, since she only had two children of her own, she treated these servant girls as daughters and even arranged their marriages and prepared their dowries.