ok so I got this Facebook friend

[Destroyer]

I don't really care for the guy but he went to my high school and I bought weed off him a couple times
here's what gets me though
dude is forever posting pro gun shit, about how fully automatic guns should be allowed and shit, usually with racist overtones
here's what kills me though
I really want to post something on his wall like 'hey bro, out of all the people who you shot and killed with guns, how many were black thugs attacking you and how many were your little sister?'
because dude accidentally shot and killed his sister when he was like 14 and she was 11 or some shit
but what I don't get, is how the fuck you could have shot your own fucking family member and still remain pro guns?
anyone have any insight as to the thought process there?