My recommendation is a Mossberg 500 20 gauge shotgun. Tell her not to hold it up to her shoulder like a rifle (unless she wants to have a good knock upside the head). Just hold it waist high and aim and fire. And go to a range and practice firing some shells and get used to the recoil. Get “home defense” shells - can’t remember the exact name but a gun dealer would know what they are.
Buckshot.
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