Caspian's Nurse

Caspian's Nurse was the first to tell Caspian X of "Old Narnia", which was the time before Caspian I conquered Narnia. She would tell him stories of Kings, Queens, Talking Beasts, and of Aslan. When Caspian told his uncle, Miraz, that she had been telling him these things, Miraz dismissed her.

She went to live with her niece and became sick. She was healed by Aslan during the Narnian Revolution, and was then reunited with Caspian.

She was one of the three people known to ride on Aslan's back (the other two were Lucy and Susan Pevensie).

Adaptations
Despite being an important part of Caspian's development and arguably central to the book's conclusion, she has not appeared in any adaptions of Prince Caspian.