Geneva Rhoden, who lost two sons, three grandchildren and a nephew, said she is begging anyone with information to step up.
"If there's someone out there that knows anything about what happened, would they please, please come forward and tell what happened," Rhoden said in the video released at family members' request by the Ohio Attorney General's Office, which is leading the investigation. "There has to be someone."
Rhoden said she has trouble sleeping and finds it difficult to be in public, often leaving stores on shopping trips when memories of things she bought for her family members overwhelm her.
The reward in the case is stuck at just $10,000, small compared to rewards offered in other high-profile killings in Ohio and elsewhere. Investigators have suggested people are reluctant to make donations because of the alleged criminal activity by one of Rhoden's sons, Christopher Rhoden Sr.
The attorney general's office has said Christopher Rhoden was operating a large-scale marijuana operation on his property.
His sister, Teresa Grebing, appeared to address this issue when she said her brothers were good people who would help anyone.
She said people afraid to come forward should just leave a tip. Southern Ohio Crime Stoppers, which offered the reward, uses an anonymous reporting system.
"I hope and pray that somebody out there comes forward," Grebing said in the video. "Please, please, please come forward. Please end this nightmare that we are living."
Saturday marks a year since of the discovery of the bodies of seven adults and a teenage boy from the Rhoden family found shot to death at four homes near Piketon, about 70 miles (113 kilometers) south of Columbus.
In addition to Christopher Rhoden Sr., the other victims were his ex-wife, 37-year-old Dana Rhoden; and their three children, 20-year-old Clarence "Frankie" Rhoden; 16-year-old Christopher Rhoden Jr.; and 19-year-old Hanna Rhoden.
Also killed were 20-year-old Hannah Gilley, who was Frankie Rhoden's fiancee; a cousin, 38-year-old Gary Rhoden; and Kenneth Rhoden, 44, Christopher Rhoden Sr.'s brother. An infant, another baby and a child weren't harmed.
Andrew Welsh-Huggins can be reached on Twitter at https://twitter.com/awhcolumbus. His work can be found at http://bigstory.ap.org/content/andrew-welsh-huggins
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