Who is Anna Van Essen/Courtney from When the Lion Feeds and what is their importance?

As a child, Anna has long brown legs, a small face framed with black hair, and a pointed chin. She has eyes for Sean from the beginning, when they attend the same school and even bribes him with her mother's well-known shortbread. When Sean rides past the Van Essen farm, she often comes running, asking to be taken along. Though Sean does not want her along at first, her naked body at a fishing hole soon changes his mind. Once she understands her power over him, the dynamics of their relationship changes. She flirts and he follows, until she finally gives in, allowing him to sleep with her before he goes off to war. Though it is a one time occurrence, Anna soon realizes she is pregnant, and her life as a child is officially over.