If I were the boys’ father, I’d wait to he gets out in about 10 years for good behavior and put a bullet in his head fro about 400 yards.
Look, no one would ever defend this mans despicable actions. But calling for vigilantism by recommending that the father resort to a vengeance murder or hoping that other prisoners would murder him is disgusting.
See the old movie "Death Wish". Why wait 10 years? Plenty of similar creeps out there to do vigilante justice on.