To Wang Guiping, a 29-year-old garment-factory worker in Fuzhou, Fujian, Children's Day is a time of sorrow and regret. Wang is separated from his nine-year-old daughter, who lives with her grandparents in their hometown of Ruichang, Jiangxi province.
Last August, the South China Morning Post uncovered a case of child sexual abuse in Ruichang in which at least seven young schoolgirls in the same class were sexually assaulted by their 63-year-old teacher, Tao Biaogong .
The girls, then aged seven or eight, were "left-behind children" who lived with their grandparents while their migrant worker parents seek better-paying jobs in prosperous coastal cities. The central government says more than 20 per cent of the country's children - some 61 million - are in such a position.
Growing up with little supervision, they can fall victim to sexual predators, drowning, traffic accidents and child trafficking.
To mark this year's Children's Day, the Supreme People's Procuratorate last week released figures about child sexual abuse from the past four years, a move legal experts described as a rare attempt to draw attention to the issue of child protection.
After their repeated sexual assaults in Ruichang, six of the girls contracted the highly contagious human papillomavirus, which causes genital warts.
Tao was sentenced by the Ruichang People's Court in October to 14 years in jail after being found guilty of molesting the second-graders between September 2012 and May last year. Tao's jail term was scant justice for the victims' parents.
"Words cannot describe my sorrow for leaving my girl behind to suffer such ordeals," Wang said.
The girls underwent painful operations last summer to remove the warts but the disease refuses to leave them alone.
"We are powerless to do anything. Because of what happened, my girl will suffer a lifetime of trauma," Wang said. Relatives and friends take the girls for medical check-ups once a month
The girls' parents have filed a civil lawsuit for compensation from local education authorities, the Tao and Shangyuan Primary School where the abuse took place, but the Ruichang court has yet to arrange a hearing date a year after the abuse was uncovered.
The Supreme People's Procuratorate's figures show the office prosecuted 7,963 cases of child sexual abuse, involving 8,069 people, from 2010 to 2013.
Over the same period, it also prosecuted 150 cases, involving 255 people, of soliciting underaged people for prostitution and 121 people for "luring children" to engage in the sex trade.
Chi Susheng, a lawyer and former National People's Congress delegate, said these figures had not been released before and would raise awareness of child protection.
"It's the first time that such specific figures have been released but they are only the tip of the iceberg."
Chi hopes an upcoming amendment to the criminal law will close a longstanding loophole that allows child-sex offenders to receive light punishment.
Having sex with underage girls is considered rape in most countries, but a controversial revision of the Criminal Code in 1997 allows offenders to admit to the lesser of charge of "soliciting underage girls for prostitution" if they can show consent or money was involved.
Chi and other legal experts have for years been calling for the charge to be abolished, saying it has led directly to a surge in sexual offences against underage girls.
Liu Wei, a lawyer from Zhengzhou , Henan province, who specialises in cases of child sexual abuse, said the prosecutors' figures showed that at least 121 people had been handed lighter sentences for raping girls.
"Giving money to children after raping them and claiming that the assault was voluntary is ridiculous and unreasonable and the law allowing the rapists to get away with lighter sentences should be abolished immediately. There is no such thing as an underaged child prostitute, and offenders are all rapists whether money or consent is involved or not," Liu said. "We'll continue to lobby until the day this law is struck off."
She said the real extent of sexual abuse of minors was yet to be revealed.
"The main reason is the extreme difficulty in gathering evidence of such abuses, as young children, especially those in kindergarten, are not able to report the trauma or express themselves clearly unless the act is caught with surveillance cameras."
Kong Weizhao, a lawyer with the Juvenile Protection Committee of the All-China Lawyers Association, agreed that the official figures underplayed the full extent of sexual abuse of young girls and boys.
"It is very common for parents to choose not to make the abuse public for fear of drawing shame … some reach a settlement with schools and even perpetrators in private. It is hard enough to obtain evidence, and our police are not trained at all to handle these cases," Kong said.
"Even when parents do press charges, the procedure of obtaining statements is made so painful by insensitive police that parents often give up halfway through, as they can no longer bear to watch their children being hurt again."
Kong called for more training for police and to allow child psychologists to assist in abuse investigations.
"I think there is progress, however slow. We hope that in October we might see the crime of soliciting young girls for prostitution abolished at the ninth revision of the Criminal Law, as the authorities, including the Supreme People's Court and the All-China Women's Federation, are now looking into the issue."