The kids' mother was shoveling the car out and put the children in the car to keep warm around 4 p.m.
Officials say it appears the exhaust pipe was covered with snow and carbon monoxide built up in the vehicle.
The kids, 4 and 7 years old, were rushed to the hospital in respiratory arrest.
Officials say both girls woke up and started crying on the way to the hospital, so it appears they're going to be ok.
The younger girl went to Bronx Lebanon and the older to Jacobi.
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