TOKYO • When Ms Yuki Kai dropped her baby off at nursery on the way to work, he was his usual bright, exuberant self. Hours later, the 14-month-old was dead.
The mother remains tortured by the questions surrounding Kento's final hours and her decision to leave him at an unofficial facility.
"Kento was found dead when a staff member went into the room to wake him from a nap. He was in a different room from the other infants because he had been crying," she told Agence France-Presse.
An autopsy proved inconclusive, but she is considering legal action.
The case caused national outrage and fears that Japan's working parents are facing a childcare lottery.
Legal expert Toko Teramachi warned that accidents involving children at non-official centres are "30 times more frequent" than those at official ones.
But the entire system is underfunded and government-approved nurseries are over-subscribed, leaving many parents to rely on other options where rules dictating class size, staff training and space are less strict.
Last year, 14 children died in childcare facilities in Japan - 65 per cent of the incidents happened in unofficial nurseries.
Experts warn that Prime Minister Shinzo Abe's bid to tackle the nation's daycare shortage by loosening requirements - such as those limiting class sizes - for even official nurseries, will make more facilities dangerous. Child welfare specialist Hiroko Inokuma said deregulation plans were "a reckless move... which could lead to more accidents" with too many children crammed into nurseries.
"You can't put your child's life in someone's hands if quality is not guaranteed," warned Ms Renho, a leading member of the opposition Democratic Party, who goes by one name.
Mr Abe has come under fire for his call for women to both bear more children to stem a falling population, and to keep working to boost the struggling economy, without providing proper childcare facilities to support this dual demand. The labour ministry estimated at least 23,000 children were unable to find an official daycare place last year.
Many parents feel they are in an impossible position. One mother, who works in public relations and asked not to be named, told Agence France-Presse that she was struggling to find a daycare solution.
She added: "I feel I am up against the wall on all sides... I simply cannot understand why Japan has not been investing more in younger generations that will eventually support all of society."