Luigi Mangione: How parents of alleged shooters cope, and therapist advice.

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As a parent, you want to do your best. You focus on your child, ensuring they're emotionally safe, properly socialized, and academically challenged — anything to set them up for success.

It's hard to fathom a dark outcome: that your child would grow up to assassinate someone, or be accused of doing so.

That's what Luigi Mangione's parents experienced last week, as the...