Willem Lannister is played by a young Northen Irish actor called Timothy Gibbons. He is a member of the Youth Theatre at the Grand Opera House Belfast and Belfast Talent Agency
The image on the page is of Martyn Lannister
Wait a minute..."Walk of Punishment":
Robb: "Willem and Martyn Lannister are fourteen years old"
Brynden: "Martyn is fifteen, I believe."
...I wondered where that came from before. So they're not twins in the TV series?....why? Simply to match the age of two actors they liked? They're fraternal twins, they don't have to look similar.--The Dragon Demands (talk) 04:43, January 16, 2014 (UTC)