Under Starry Skies — Judy Ann Davis

Hired as the town's school teacher, Maria O'Donnell and her sister Abigail arrive in the Colorado Territory in 1875, only to find the uncle they were to stay with has been murdered.
Rancher Tye Ashmore is content with life until he meets quiet and beautiful Maria. He falls in love at first sight, but her reluctance to jeopardize her teaching position by accepting his marriage proposal only makes him more determined to make her part of his life.
When their lives are threatened by gunshots and a gunnysack of dangerous wildlife, Tye believes he is the target of an unknown enemy. Not until Maria receives written threats urging her to leave does she realize she is the target instead of the handsome rancher.
With the help of Tye, Abigail, and a wily Indian called Two Bears, Maria works to uncover her uncle's killer and put aside her fears. But will she discover happiness and true love under Colorado's starry skies?