The one child policy always exempted minorities and rural people (and other misc exemptions). In 2013 the policy was changed so that families could have two children if one parent is an only child. They don't have formally arranged marriages to the same extent as in India, but the parents often get involved in trying to find a suitable match. Culturally, fat babies were seen as healthy, but as they get older the extended family (i.e. aunties) would shitlord in front of everybody if the fat was retained.