Story highlights The 3-year-old is in his grandmother's custody

The uncle was charged with endangering the welfare of a minor

(CNN) When you hear of peer-pressured pot smokers, you picture first-year college students or coming-of-age teens, not toddlers. That's why a video that police say Lamel Yancey of Arkansas uploaded to Facebook is causing furor online. It shows Yancey urging a diapered, 3-year-old to smoke a joint.

The boy is Yancey's nephew, police said.

In the video, Yancey hands off the joint to the boy in the back seat of a car.

"You want to hit the blunt, man?" Yancey asks the toddler.

The boy inhales and coughs.

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