Elissa Robinson

Detroit Free Press

MUSKEGON, Mich. — Police are investigating the death of a 1-year-old boy found dead at a Muskegon day care center and an 8-year-old girl may be responsible.

The child's mother, Bryanna Reasonover, says she left work to pick up the toddler and two other kids around 7 a.m. Friday. When she arrived, she says her son, Korey Brown, was laying in a playpen, unresponsive.

Early investigations reveal there were adults in the home, but the children were left unsupervised for an unknown period of time, Muskegon Police Chief Jeffrey Lewis told WZZM-TV (Grand Rapids). It's believed Korey was crying about something when the other child stepped in to help.

It's likely that process cost the child's life, Lewis said.

Lewis says the girl is now a suspect in the case and the prime witness is 5 years old.

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There were four children being cared for in the home, the youngest being 1 year old, the oldest being 8 years old.

Lewis said the Korey's body had no obvious injuries. Reasonover said she noticed bites and bruises on his face.

"It's very frustrating to not know what happened, to know that he was suffering when all he probably wanted was his mommy," Reasonover said.

Reasonover described her son as a joyful baby who just started walking a few weeks ago.

The 8-year-old child is being interviewed by police, according to Lewis. It's unclear where the child will stay during the investigation.

No official cause of death has been released and police have not released the name of the child care center.

WZZM-TV (Grand Rapids) contributed to this report.