What are your thoughts on the two girls that tried to commit murder on behalf of Slenderman?

In the documentary “Beware of Slenderman” two girls, both aged 12 years old, stabbed their friend 19 times leaving her to die. They did this in the name of an internet myth by the name of “Slenderman.” What do you believe was the cause of this incident? Do you think the outcome of their sentence is fair? Do you think it was right for them to be tried as adults? Do you agree with the girls trying to get a lesser charge for their crime?

The girl that was stabbed is named Payton Luetner. She is 15 now and doing well for herself.