The fact that they stabbed someone to "protect their family" is already telling me that they were stupid enough to think that slender man was real! I don't know a whole lot about slenderman but i do know that he is as fake as you can get. So ,yes I think those 12 year olds should be tried as adults.
Morgan has schizophrenia, which impairs ones judgement severely. When you’re a child you are much more gullible and easily pressured. Morgan fully believed in Slenderman and that she and Anissa had absolutely no choice but to kill their friend. Anissa was simply convinced by her. I recommend watching the slenderman documentary: Beware The Slenderman. These girls aren’t monsters. They need serious therapy.