Peace and healing to you and your family, and may the unfortunate man rest in peace.
Your question about what sort of shopkeeper sells a gun to such a person is certainly to the point. The probable intent of the purchase could not have been missed.
In a heartbreaking situation such as this parents simply have to go with what their best instincts tell them.
“Most of all you’ve got to hide it from the kids”
-Paul Simon
You started me thinking of something in my own family. Not that I don’t think of it nearly every day. When my brother was incarcerated he and his wife told the grandchildren that he went to take a job in Detroit — a city sufficiently distant from Florida (where they live) to seem almost like another planet. Their situation involves a deliberate lie told to children in order to avoid a shameful truth. He is on parole now and I ask him periodically when/if he plans to own up to them. I point out that they are twenty-first century children and may well stumble upon the truth. Would he prefer that? Perhaps they already have! I point out that they will hate him anyway so why drag it out, and was it really such a great idea to add lying to his catalog of sins? His (now ex-) wife interviewed the grandchildren extensively in order to satisfy herself that he had not inappropriately touched them, as did the authorities, providing a “way in” so to speak for the truth, had anyone had the guts.
Looks like I’ve gone on rather long, sorry.