UPDATE: 3-year-old killed in family's driveway, possibly with dad at wheel instead of sibling accident

HOUSTON, Texas (KTRK) -- Deputies are investigating a tragic deadly accident that occurred Tuesday morning in the 6300 block of Logan Creek in Fort Bend County.

According to the Fort Bend County Sheriff's Office, just after 10 a.m., a father started the family vehicle in order to run the air conditioning and cool off the vehicle as he put his children in their car seats.

Initially, deputies said that it appeared that when the father ran back into the garage to grab something, the 3-year-old apparently got out of the car and the 4-year-old climbed from the back seat to the front seat, knocking the vehicle into gear. Now deputies say that may not be the case. Instead, the girl's father may have been in the driver's seat.

The vehicle ran over 3-year-old Dia Nebhnani. Deputies and EMS crews were unable to save the preschooler, who died at the scene.

Authorities are reviewing surveillance video to determine the sequence of events, but stress that they don't believe the father was lying. They say he was understandably distraught, and there was a language barrier.

They are also conducting a blood test.

Child killed when sibling puts vehicle in gear while father was cooling off car in the driveway

The accident remains under investigation.

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