Did you read what was written on the scroll?
I can help.
"Robb, I write to you with a heavy heart. Our good king Robert is dead, killed from wounds he took in a boar hunt. Father has been charged with treason. He conspired with Robert’s brothers against my beloved Joffrey and tried to steal his throne. The Lannisters are treating me very well and provide me with every comfort. I beg you: come to King’s Landing, swear fealty to King Joffrey and prevent any strife between the great houses of Lannister and Stark."
