They then broke in there, beat up the gang members girlfriend, pushed the gang member out a window, stabbed the younger brother in the arm, then shot them all after interrogation and torched the house, setting the neighbor hood on fire.
The younger brother was 15...
I need to instil some humanity in my players...
Many fun ideas from people before this post. Take inspiration where you may!
Funny story that's relevant:
Some few years ago, back when I was in my SR prime, the team's Decker sort of had this very strange thing wherein he'd sometimes carelessly leave his cyberdeck lying around (nobody ever understood why). So, inevitably, this one time, he goes and retrieves it only to find it had gone missing. The Runners team up with him to track down the thief which eventually leaves them out into the sewers.
Soon enough, they come upon something of an alcove whereupon a bundle of blankets and covers seems asleep what with steady breathing and the form rising and lowering rhythmically. The Deck's in plain sight, slightly a-ways a good third of it sticking out from beneath the bundle. Now, you can imagine the Decker was pissed off, so, without much thought other than retribution, he empties his APDS-filled Ingram Smartgun on the sleeping form. Retrieving the deck, he tosses the blankets... only to see a mucked-up and quite dead sleeping ten year old kid.
This would have been the beginning of a plot-hook with that particular street kid having more street sense than most folk (sort of, but not immediately, inspired by the character "Newt" in the movie
Aliens). As a GM, I learned a valuable lesson: having important gear stolen from careless Runners is possibly not the better way to start up a scenario. As a player, the Decker learned that not everything in Shadowrun is about shooting first and asking questions later.
But, yes, you mention your group gladly shanking a 15 year-old. That may demand a bit more attention to hammer into them a sense of realism in that the characters they portray ought to "feel like actual people" and the persons who people the game world should also feel real enough to be convincing. If you manage this, then maybe they will begin to feel a bit more humane -- or, at least, more sympathetic towards others.
Regardless, teaching them a messy lesson involving an angry ghost or specter (or possibly also involving some fun with their remains returning as Corps Cadavre hounding the PCs -- the ghost of your 15-year-old might've struck a pact with someone (or some thing)). Make it fun, feel free to harass the characters, take the time to have the lesson taught, build on it (might be something you want to stretch out into subsequent storylines -- not the ghosties or beasties, but maybe they'll attract the attention of someone or some thing that's Karma Incarnated) but remember to have fun, for yourself and your players.
Or!
Have that 15-year-old be friends with my Street Sammy Elf Girl Who Has A Thing About Protecting Street Kids And Who Has Vowed To Avenge The Death Of Her Friend (kidding
)!
