Authorities in Nebraska are investigating the death of a 20-month-old toddler who was in foster care.

Nathaniel Saunsoci-Mitchell was a member of the Omaha Tribe. He was placed in foster care by the tribe while his mother, 18-year-old Jackie Saunsoci, went through drug and alcohol rehabilitation.

The foster family lives in South Sioux City, off the Omaha Reservation. Olivia Saunsoci, the toddler's grandmother, said the foster parents were neither Omaha nor Winnebago.

Saunsoci-Mitchell died on Sunday after being treated at two hospitals. His body showed signs of trauma. Preliminary results show his death was not from natural causes.

Olivia Saunsoci said the incident has "caused a lot of panic on the reservation," The Sioux City Journal reported. She said tribal children shouldn't be placed in foster care off the reservation.

Get the Story:
Toddler dies of injuries (The Sioux City Journal 9/27)
Toddler's Death 'Not From Natural Causes' (KTIV 9/26)