Rickon Stark

Rickon Stark is a supporting character in Game of Thrones. He was played by an unknown extra in the pilot episode and is likely to be recast for the full series.

Rickon Stark is the youngest son of Eddard and Catelyn Stark and the younger brother of Robb, Sansa, Arya and Bran, as well as the younger half-brother of Jon Snow.

In the books
In the Song of Ice and Fire novels Rickon is three years old when the action begins. He is very young, but fierce and strong for his age.