Ten-year-old Tionda and 3-year-old Diamond had left a note, saying they were going to the store and the playground.
Intense searches and pleas to the public have failed to turn up any leads.
On Monday evening, the family of Tionda and Diamond held another vigil to remind the community that the two girls have not been found.
"They would be intelligent young women, one just graduated, the other getting ready to go through middle school," said Mary Bradley, Tiona and Diamond Bradley's grandmother.
Bradley says the past eight years have been a struggle and that every day she wonders about her granddaughters who disappeared from their South Side apartment in 2001. It's caused a heartbreaking mystery that the family is still hoping to solve.
"It's been really, really hard, frustrating, no information or anything," said Bradley.
Tionda would be 18 this year and Diamond would be 11. Since their disappearance, the Bradley family has persisted in keeping their names in the news in hopes that someone with information about the sisters will step forward.
Over the years there have been a few developments. The discovery of human remains and possible pictures of them on the internet proved to be false leads.
Mary Bradley says she will fight for them until she has closure.
"For me, whenever if I go outside talking, I try to spread the word. But it's just stressful. It is. It takes its toll every day," said Bradley.
The family has held a vigil in past years as well. On Monday evening, they were going to release balloons in memory of the two girls and hold a prayer vigil.
As for the latest on the investigation, the Chicago Police cold case unit is investigating the disappearance. They have policemen actively working this case but there are no new developments.