Him being arrested for threats and expelled won't forget up his future? Oh he'll yes it will. Arrested at the age of 13?
Uh, no. That's not how that works. At worst he'll get detention or a stern talking to or some stuff. You can't be arrested under the age of 18.
Also no, you won't break any bones. By that I mean neither of you are capable of that.
It's middle school. Nobody's life is going to be "forgeted up". You're both going to get a slap on the wrist and that'll be the end of it.
This, essentially.
He threAtened me on facebook, screenshot proof, I'm good friends with the head of gang activity cop bro. He'd get arrested.
You can't be arrested for anything under the age of 18, save for federal offenses and felonies like grand larceny and murder. (And even then you're not arrested, you'll be put in the juvenile corrections system)