Jeyne Poole

From Asoiaf

Jeyne Poole is daughter of Vayon Poole, steward at Winterfell (GoT, App)

She was Sansa's dearest friend.

Queen Cersei brought Princess Myrcella to stich together with Arya Stark, Sansa Stark, Beth Cassel and Jeyne Poole, overseen by Septa Mordane. The girls discussed Prince Jofferey, who Sansa was going marry, and Jon Snow. When Septa Mordane critized Arya's crooked stiches, she ran out of the room.