Lady Tressilian

Lady Tressilian is the name of two different characters in the works by Agatha Christie, both of who live in or near St. Loo:
 * Lady Tressilian (The Rose and the Yew Tree)
 * Camilla, Lady Tressilian (Towards Zero)

A third woman shares the same name, but it is spelled differently:
 * Lady Tressillian (Five Little Pigs)