Nothing happens the government stick to there plans, if you have two children (twins) and there both male you can keep them if one is female she will be killed/drowned ect...... This is calledf One Child Policy in China
As China is no. 1 country on the basis of population so the government in China bring a policy of two children to control the population of their country.Under this policy no people in china has more than two children either they will be punished or they will charged some money.
Some people people feel that the one child policy s helping China provide space for its citizens to live but the parents who have 2 or more children might think that it is bad because they will be losing their kids.