Anna Craig was an elderly woman, a member of the congregation of the town of Walnut Grove.
After a time, she falls in love with the Reverend Alden. She invites him to her house and tells him so. At first, Reverend Alden takes her statement as an expression of Christian love, not as a personal romantic interest between a man and a woman. He panics and quickly withdraws. She and Reverend Alden had a wedding planned until the local Church congregation intervened and called a meeting on the matter. (Episode 606: The Preacher Takes A Wife)