Endangered words

In Mandarin there is greater variety of titles for family members. In stead of 'brother,' 'sister' or 'sibling' there's big sister [jie Jje], little sister [mei mei], big brother [ge ge] and little brother [di di]. They are cute designations of relativity to relatives. When my dorm mate said her mei mei was coming I thought nothing of it except, 'how sweet.' But later I realized that those words are rarely used here as a nation of singletons does not have a ge ge or jie jie; there's been a one child policy in place since the '70's. My roomie doesn't look old enough to predate that rule. Is she a twin? Does she belong to a minority ethnic group that allows acceptations to the rule? Were the parents natal outlaws? None of the above. In reality she was a cousin. Mei mei still sounds better to me.

Beijing, China