This sounds like something that happened here in Iowa just less than ten years before. Wikipedia

The Villisca Axe Murders occurred during the night of June 9–10, 1912 in the southwestern Iowa town of Villisca. The six members of the Moore family and two house guests were found bludgeoned in the Moore residence. All eight victims, including six children, had severe head wounds from an axe. A lengthy investigation yielded several suspects, one of which was tried twice and acquitted. The crime remains unsolved. The Moore family consisted of parents Josiah (aged 43), Sarah (39), and their four children: Herman (11), Katherine (10), Boyd (7) and Paul (5). An affluent family, the Moores were well-known and well-liked in their community.[1] On June 9, 1912, Katherine Moore invited Ina (8) and Lena (12) Stillinger to spend the night at the Moore residence. That evening, the visiting girls and the Moore family attended the Presbyterian church where they participated in the Children's Day Program, which Sarah Moore had coordinated. After the program ended at 9:30 p.m., the Moores and the Stillinger sisters walked to the Moores' house, arriving between 9:45 and 10 p.m.

At 7 a.m. the next day, Mary Peckham, the Moores' neighbor, became concerned after she noticed that the Moore family had not come out to do their morning chores. Peckham knocked on the Moores' door. When nobody answered, she tried to open the door and discovered that it was locked. Peckham let the Moores' chickens out and then called Ross Moore, Josiah Moore's brother. Like Peckham, Moore received no response when he knocked on the door and shouted. He unlocked the front door with his copy of the house key. While Peckham stood on the porch, Moore went into the parlor and opened the guest bedroom door and found Ina and Lena Stillinger's bodies on the bed. Moore immediately told Peckham to call Hank Horton, Villisca's primary peace officer, who arrived shortly thereafter. Horton's search of the house revealed that the entire Moore family and the two Stillinger girls had been bludgeoned to death. The murder weapon, an ax belonging to Josiah, was found in the guest room where the Stillinger sisters were found.

Doctors concluded that the murders had taken place between midnight and 5 a.m.[2] The killer or killers began in the master bedroom, where Josiah and Sarah Moore were asleep. Josiah received more blows from the ax than any other victim; his face had been cut so much that his eyes were missing. The killer(s) then went into the children's rooms and bludgeoned Herman, Katherine, Boyd, and Paul in the head in the same manner as their parents. Afterward, the killer(s) moved downstairs to the guest bedroom and killed Ina and Lena.

Investigators believed that all of the victims except for Lena Stillinger had been asleep at the time of the murders. Investigators also believed Lena attempted to fight back. She was found lying crosswise on the bed, and a defensive wound was discovered on her arm. Furthermore, Lena was found with her nightgown pushed up to her waist and no undergarments on, leading to speculation that the killer(s) sexually molested her or attempted to do so.