It has taken Xu four months to find the first wish, after making hundreds of calls, searching numerous posts online and lots of talking. It has been from an 18-year-old girl with leukemia, who dreamed of entering the China Academy of Art. Persuading her family, Xu helped the girl to get an opportunity to study at a painting studio for free in Hangzhou when she got better.

The girl received a transplant in April 2017 and three months later, she started painting in the studio.

A study on the effects of the wish-making intervention on psychiatric symptoms and health-related quality of life of children with cancer published in Quality of Life Research in 2015 showed that children who experienced a wish coming true demonstrated a greater health-related quality of life, with a significant reduction in their perceptions of their own physical limitations.

Childream has volunteers across the country. To reach more children, it has opened accounts on social media platforms, including Sina Weibo, Bilibili and Douyin. It has made national headlines for its wish-fulfillment deeds, from fanciful to practical.

Some children like 5-year-old Yi want to meet their favorite anime character or celebrity, such as Ultraman; some want to experience a day as a police officer, firefighter or racing car driver; some wish to travel to somewhere; and some want to open a concert.

Some wishes need the participation of thousands of people. In 2017, under the coordination of Childream, tens of thousands of people in Hangzhou helped two sick children－Jin Qianzhe, 8, and Mao Xu, 9, both with Prader-Willi syndrome, a genetic disorder that affects development－to fulfill their dreams of becoming a police officer and a doctor for one day.

"These wishes are just like light, which can drive out the darkness, and granting the wishes can help these children to see hope and love in their life," Xu says.