One child is dead and another seriously injured after a fire in their Hermon mobile home Tuesday morning.

The State Fire Marshal’s Office said a third child escaped the burning home and flagged down motorists to help. The fire at 292 Wing Road in Hermon was first reported about 7:15 am. Tuesday.

The mobile home was occupied by John Parker and Lasey Reidy, who had left the children alone after getting up to do errands.

Wyatt Parker, 9, of Levant, died in the fire; his body was found in the living room. He had spent the night with his cousins Ashlyn Parker, 10, and John Parker, 8. Ashlyn was rescued from her bedroom by firefighters and was taken to Eastern Maine Medical Center for treatment for smoke inhalation. She was in critical condition when she was admitted to the hospital, but by Tuesday afternoon, officials said Ashlyn’s condition had improved.

John and Ashlyn are the children of Parker and Reidy. Wyatt was Parker’s nephew.

Parker and Reidy returned to the mobile home as firefighters arrived. Five fire marshal investigators are trying to determine the cause of the fire, which is believed to have started in the kitchen. The mobile home was equipped with smoke detectors but investigators were not sure they were working.