The death of a 2-year-old boy while under the care of a baby sitter in Saitama Prefecture highlights the need for measures and systems to ensure that parents can leave their children with reliable parties, experts say.

According to reports, the child's mother, a resident of Yokohama, hired the man through an online baby-sitting broker website, and that the boy and his 8-month-old brother were kept in the man's apartment in Fujimi, Saitama Prefecture. The mother apparently barely knew who the man was.

Akemi Morita, a Toyo University professor of child welfare, stressed the need for a system to vet baby sitters.