Born in Cheyenne, Wyoming, Patricia Pritzkau spent several years in Minnesota before moving to the East, where she graduated from the University of Connecticut. She later taught English, married Robert MacLachlan, and had three children.
During this time, she wrote a series of journal articles on adoption and foster mothers that had a major impact on her life. She says, "It was clear to me that much of the focus of my writing was sharpened by my involvement and concern for families and children. This interest, coupled with my commitment to children's literature, provided the basis for my decision to write for children—something I had always wanted to do."
Patricia MacLachlan was born on the prairie, and to this day she carries a small bag of prairie dirt with her wherever she goes to remind her of what she knew first. She is the author of many well-loved novels and picture books, including Sarah, Plain and Tall, winner of the 1986 Newbery Medal; its sequels, Skylark and Caleb's Story; and Three Names. She and her husband live in Williamsburg, Massachusetts.