Dropped on the floor ~ frequently little kids are not strong enough to hold the firearm up very long. That, BTW, is an argument for establishing a lower weight limit for weapons ~ so that if kids get hold of them they can't use them.
I somehow doubt that a woman would carry a weapon in a purse that was so heavy that a child could not point it briefly, "just to test it."
If it was that heavy it would not have rested unrecognized in her purse.