Wu has long been concerned about the mental wellbeing and inter-generational upbringing problems of the elderly. The emotional and psychological problems of some elderly people largely derives from the anxiety in bringing up a baby, he says.

"With the second-child policy, the number of elderly people with various emotional disorders has really been increasing.

"The anxiety and other negative emotions of the elderly can easily be passed on to the children and other family members. This inevitably leads to tensions in the family's interpersonal relationships, especially conflict between mothers-in-law and daughters-in-law."

Unlike with young people, the emotional disorders of the elderly are often manifested in various physical discomforts, and some will feel tightness in the chest, palpitations, stomachache, feeling bloated and other symptoms, which are often related to mood swings, Wu says.

Often when elderly people report not feeling well, a physical examination finds no organic cause, because at the root of it is a psychological problem, Wu says.

Zhang Xiulian, 68, says she has been feeling down lately, whereas she always used to be talkative and loved to laugh. Her daughter-in-law in Beijing, who has one child, was recently expecting a second, and plans were made by her and the father to ask Zhang to take care of the baby in Beijing.

Zhang says she lacks the physical strength compared with five years ago when she helped raise the couple's first child. She was also hesitant about leaving her husband behind in Hebei province and wanted to pay for her son to recruit a nanny in Beijing. But the son said that in Beijing a 24-hour-a-day nanny costs too much, and after to-ing and fro-ing the daughter eventually had an abortion.