|In around 290 AC
Rosamund is a child with straight yellow hair.
Rosamund accompanies Myrcella Baratheon as a handmaid when the princess goes to Dorne. She is chosen by Tyrion Lannister, the acting Hand of the King, to accompany Myrcella due to similarities in height and looks from afar, although Rosamund's hair is straight while Myrcella's is curly. Because of the risk of the Seaswift being taken by Stannis Baratheon's forces on the way to Braavos, Septa Eglantine puts brown dye in Myrcella's hair to disguise the princess, and Rosamund wears her clothes.
A Feast for Crows
Rosamund is enlisted in Princess Arianne Martell's plot to crown Myrcella as queen. Myrcella curls Rosamund's hair, dresses the handmaid in her own bedrobe, and paints dots on the girl's face so it appears she has redspots. Ser Arys Oakheart tells Maester Caleotte about the redspots, and the maester keeps away to avoid contracting the disease as an adult.
Rosamund doesn't truly favor me, but when she dresses up in my clothes people who don't know us think she's me.