Editor's note: HLN is airing a special "Nancy Grace: America’s Missing" with the goal of trying to find 50 people over the next 50 days.
Nancy Grace will take a look at several cases around the nation in hopes of helping to solve them. This was the fourth case.
[Updated Friday at 9:41 a.m.] Ten-year-old Tionda Z. Bradley and her sister, three-year-old Diamond Yvette Bradley were last seen on July 6, 2001 in Chicago, Illinois.
Their mother told police the girls were accustomed to being home along because she was a single mother and when she left that morning they were asleep on the couch, where it was comfortable in the summer.
But when she came home she found a note her oldest daughter wrote saying she was going to a store, then the school playground. They were last seen playing in the neighborhood, but nobody has ever seen or heard from them since.
"I believe that someone that was in close acquaintance with the mother of Tionda and Diamond took those children," Shelia Bradley-Smith, the girls' great-aunt told Nancy Grace. "The note, that was not the way Tionda spoke ... she was coached to write that note."
She also said there was a voicemail that said that "George was at the door."
An extensive search was launched by the girls' home, a nearby lake and even the cellar of the abandoned New Hope church - but they found no clues and the case remains unsolved.
For more information on the sisters, their description, and information to contact authorities, visit Nancy Grace's blog.
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