LONGWOOD, Fla. - Jackie Sheehan was 31 years old when she was found dead in a wooded area in Longwood in 1998.
Investigators said her boyfriend at the time was the last one to see her alive.
Fifteen years later, her family said they're still trying to heal.
Detectives said that when they found Sheehan's body, it was so badly decomposed they didn't know if it was a man or a woman. Investigators used jewelry to identify her.
Her sisters said they believe they know who is responsible, but detectives need more evidence or a confession for an arrest.
Linda Call, one of Jackie Sheehan's sisters, said things get better with time, but they still don't have closure.
"She was such a beautiful person," Call said.
Sister Nancy Sheehan said they didn't believe she was really gone.
"None of us did," Nancy Sheehan said.
At the time, Jackie Sheehan lived only about two miles down the road from where she was found.
Her then-boyfriend and their two children, who are now both teenagers, have since moved out of state.
Her sisters said they do not have contact with them.
"We want justice, we want justice still to this day, as much as (we) did when it happened," Call said.
Jackie Sheehan's sisters and the Seminole County Sheriff's Office are asking the public for new leads to help find her killer.
They hope someone who knew her or one of the thousands of people following her case on Facebook will help lead to an arrest.
"Even if they don't think it's anything, it could help," Nancy Sheehan said.