From YahooNews: 

Mich. boy, 5, takes off in grandma’s SUV

YPSILANTI TOWNSHIP, Mich. - A 5-year-old boy hopped behind the wheel of a sport utility vehicle and drove it several blocks looking for his mother following an argument with his grandmother, authorities said.
 
The child was not injured in his short drive last Wednesday, and his grandmother’s 2004 Cadillac Escalade was stopped without incident.

The boy, whose full name wasn’t released, started the truck, cranked up the stereo and stood on the driver’s seat to see over the steering wheel, Washtenaw County Sheriff’s Cmdr. Dave Egeler told The Ann Arbor News.

The boy told sheriff’s deputies he was “looking for his mommy,” police reports said. He was not expected to face any charges.

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