The contemporary Australian writer Marion May Campbell has composed many works reflecting complicated modern social issues. Her third novel Prowler focuses on the family life of Tom-Tom by flashbacks and interludes to review her short life. Tom-Tom grows up in a non-nuclear family without parental care having been raised by her loose-minded grandmother alone. She is not capable of defining the ethical identity and always makes wrong ethical choices in her marital life. As a result, her first marriage is terminated by divorce and the second is evaded by silence. Eventually, she picks up courage to take the responsibility in seeking ethnic identity, which helps her succeed in constructing the ethical identity. In the story of Tom-Tom, it is easy to detect that a good ethical environment makes a great difference for individuals to recognize ethical identity and assume ethical responsibilities, which provides a good example for contemporary marriage and family life.