A large group gathered at Taylor Park on Chicago's south side to say a prayer for the Bradley sisters.
They were three and ten years old when they disappeared from their Bronzeville apartment in 2001.
"We're still praying... having hope that Diamond and Tionda return home to our family and friends," the sisters' mother, Tracey Bradley, said.
Saturday's event ended with a balloon release for the missing girls.
The family asked anyone with information to come forward.
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