"But science can change their situation. Supported by a cochlear implant (an electronic device surgically placed in the cochlea), they can get signals from others and reply to help the movement of their vocal cords and they can even sing," she adds.

Many children have recovered from their condition with such help in primary schools exclusively for them, and have entered middle school along with their teenage peers who can hear normally.

"But I found that many of them face difficulties in middle school because they lack self-confidence, and the care from teachers in normal schools isn't similar to that given in the special primary schools."

Xiao says these were reasons why she founded the choir. She hopes to give the children an equal platform with their peers in society and present their skills.

During their performance on Sunday, the parents joined their children as a part of a song. The purpose of this arrangement was to give encouragement to families, not just the children.

"Many of the families with disabled children have their own struggles. But some parents don't even allow their children to appear in front of neighbors, because of stigma attached to such conditions," Xiao says. "Many mothers blame themselves. Such an approach isn't healthy."

The choir has some 40 volunteers who help the children with their singing.