I am unfamiliar with Nunez's work but I know another Sigrid, so my first degree is the epic historical novel Kristin Lavransdatter by Sigrid Undset, set in 14th century Norway and written in 1920.
The link to my second degree is Norway: Mama’s Bank Account by Kathryn Forbes (1943) is about a Norwegian-American family living in San Francisco, It is a delightful fictional memoir about the author’s childhood growing up in the boarding house her mother ran. One shockingly memorable bit was an eccentric uncle who used to yell, “What are Swedes but Norwegians with their brains knocked out?” My mother says the TV show based on this book is one of the first things she remembers watching in the 50s.The Ninth Guest (fka The Invisible Host), with her husband. It looks like the closest copy is at UNC so I am not sure this Duke alumna can pursue it . . .
My fifth degree is another heroine named Tessa in Love You More by suspense writer Lisa Gardner (2011). Tessa Leoni is a state police trooper in Massachusetts accused of killing her abusive husband. Her six-year-old daughter is missing and Tessa is terrified that the police won’t search for the girl because they are so busy building a case against her. I also just finished Gardner’s most recent book, Before She Disappeared.Abuse is the link to my sixth degree, Dune Drive by Mariah Stewart (2018) about a woman who realizes she is in an abusive relationship and plots to escape. She takes refuge with her grandmother in a coastal community in Maryland, where she rebuilds her life and falls in love. Naturally, the evil ex is looking for her everywhere so I cringed when Chrissie allows someone to take her picture.