I'm struggling to control my teen's screen time. I'm worried about who he'll become if he spends all his time on his phone.

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• When my son was young, we had strict rules for screen time, and he followed them all.
• Now that he's a teen, he turns to his phone for comfort and spends most of his time on screens.
• I'm worried he will become unmotivated, so I'm trying to get him out of the house more.

Every parent who has bestowed a smartphone, gaming device, or some other form of...