The Macroeconomics of Chinese kleptocracy 14 years ago
In China, a married couple who are both only-children can actually have 2 children. This was an alteration to the policy made in 2010 and was exactly designed to stop the 4 grandparent problem.
Ref: http://www.cbc.ca/news/world/story/2009/10/28/f-rfa-germain....