According to Duan, there are 1 million bereaved parents in China. And most of these elderly parents are over 50 years old.

The elderly can stand only so much trauma in their later years.

"The loss of their only child killed their hopes", says Duan, adding that as a result the bereaved parents are likely to isolate themselves from the outside world.

"They feel uncomfortable especially when other relatives talk about their children."

Duan helps more than 1,000 bereaved parents and over 200 of them are part of the art troupe where activities like a spring outing, birthday parties and classes like hulusi, tai chi and dancing are held.

Liu, 65, who lost his only child, says that he has learned to use WeChat and takes part in various social activities with the help of volunteers.

Duan says that the "negative energy" in socially vulnerable groups does not affect him.

"As a counselor, I know the boundary between life and work.

"I sympathize with them but won't intervene unnecessarily."

In October 2010, Duan founded the Baoji Siyuan Psychological Research Institute and organized psychological experts and scholars to carry out mental health research and voluntary service.

And in November 2012, he set up the Baoji Mental Health Industry Association, promoting specialization and professionalism in psychological counseling and volunteer work.

Also, thanks to Duan's efforts, the local government is now focusing on the training of psychological counselors and the setting up of psychological counseling rooms in schools, communities and enterprises.

Duan says psychological counseling can't be done in one stroke. In fact, some need two to three months, or even a year to recover.