The step up from "STFU" because "STFU" just causes you to lose the right to talk where as "Go to Bed" takes away your right of consciousness for that day. Being told this is considered extremely offensive, and it is abbreviated to "GTB" for easier use on forums and other things involving the internet.
Eaxample 1:
Person 1: I could 0wn you with my level 45 paladin n00b!
Person not 1: Go to Bed Neine Fro!
Black mama:YALL KIDS NEEDA GO TO BED BEFORE I WOOP ALL YALL ASSES OKAY BENN SHAWN AND MARCOES OKAY!!
mama:so ben you wanna eat chips
Benn:im sorry mom
Mama:whoops benn ass
Shawn:starts twerking on marcus.
Marcus:pushes shwan off the bunk bed and he dies.
Benn:*still getting his ass beat* damn
Mama:now YALL needa go to BEDD