Andrew Sandstrom piled the six kids — ages 7 and under — into the family minivan Tuesday and dropped his wife off at work, then returned to their Moorhead apartment.
Four hours later, Sandstrom realized that the family's youngest, 5-month-old Christiana, was still in the van. He went back, got her out of her car seat and brought her into the apartment. She couldn't be revived.
Police say Christiana died at the scene Tuesday night in what they believe is another case of a child left in a hot vehicle.
"We realize they are in heavy grieving right now," said Police Lt. Tory Jacobson, of 24-year-old Andrew and Shayna Sandstrom, 27, and the children they are raising at the apartment in the 1100 block of 19th Street S.
Jacobson said his department will investigate Christiana's death and forward their findings to prosecutors for possible charges, but called it "an accidental death" caused by the father simply forgetting he had left the baby behind in her car seat.
Jacobson said the investigation would reveal details, such as whether the van's windows were closed.
Temperatures in the Moorhead area climbed into the low 80s by late afternoon and into the early evening Tuesday, according to the National Weather Service. Andrew Sandstrom called police about 8:20 p.m.
"It's so tragic," Jacobson said, "even with windows that would be cracked open, clearly, we all know that a vehicle that isn't running with the air conditioning on," can heat up sharply and quickly on the inside.