During the initial argument, the stepson appears to have struck Pawloski several times and possibly tried to strangle him, police said, adding the older man had marks on his neck and face. The two separated and went to their own rooms, authorities said.

However, a few hours later, the stepson went into Pawloski’s room. Bois said the conversation between the two men was initially apologetic, but quickly turned argumentative again.

Around 4:45 a.m., when his stepson was about to begin striking Pawloski again, Pawloski pulled out a gun and fired twice into the man’s chest, according to police.

via Police: Elder abuse victim killed stepson in self-defense – San Antonio Express-News.

And this was not the first instance where the step-idiot had attacked the older gentleman as he had a previous arrest for the same thing.

Domestic abuse can be cured. Some remedies are extreme but assure no recidivism.