I
After the quake, The parent lost their own child.
II
The place of the earthquake is a test case of the one-child policy. So many parents lost their own child in the earthquake in 2008. After the quake, the Communist party recede the propaganda of the policy but banned the news about it.
III
This policy may be made China less productive, some people fired and lose their job because of this policy, it is crazy.
IV
The author followed the couple went from their working place in Beijing to Sichuan, to found the clue of their daughter.