CHICAGO (CBS) — Even after 17 years, the Bradley family has not given up hope of finding Diamond and Tionda, two sisters who vanished without a trace in 2001.

Tionda and Diamond were 10 and 3 when they disappeared from their apartment near 35th and Cottage Grove on July 6, 2001, while their mother was at work.

Their mother found a note on their back porch, saying the girls were going to school and a nearby store.

Police launched one of the biggest manhunts in Chicago history after the girls disappeared, searching open fields, railroad cars, and 5,000 abandoned buildings. It mostly turned up nothing.

Today, Tionda would be 27, and Diamond would be 20. Over the years, the family has continued to release age-progressed pictures to show how the sisters would look now. The most recent age-progressed pictures were released last August.

These are the latest “age progression” drawings of the long-missing Bradley sisters: Tionda, left, who would be 26, and Diamond, who would be 19. (National Center for Missing and Exploited Children/Shelia Bradley-Smith)

In 2008, a private detective concluded that a mysterious Internet picture that appeared on a MySpace profile was, in fact, Tionda Bradley; but that conclusion later proved incorrect.

Their mother has long since moved away from the Bronzeville neighborhood where the girls were last seen, and has changed her phone number.

The sisters’ great aunt, Shelia Bradley-Smith, said several years ago that she got in touch with the family that now has that phone number to let them know about the girls, just in case Tionda ever dialed the number that used to be hers.