A new search is under way for missing schoolgirl Arlene Arkinson, who vanished in 1994.
Police today sealed off an area outside Castlederg, Co Tyrone, where she was last seen.
The missing poster of Arlene Arkinson. A new search for her body is under way.
Her sister Kathleen said: "I'm hopeful, but then again I'm afraid to build up my hopes too much because I've been let down so often."
Arlene went missing after returning home from a disco in Bundoran, Co Donegal, with serial sex attacker Robert Howard, who was cleared last month of her murder.
Tracker dogs were used as police examined land near a two-storey house on the Drumquin Road. The area has been checked before as part of a series of searches around Castlederg and in remote countryside along the border between Tyrone and Co Donegal.
According to Kathleen, Arlene was in Howard's blue Metro car on the Drumquin Road before she disappeared.
Child abuser and rapist Howard (61) was sentenced to life for the murder of English schoolgirl Hannah Williams, whose body was found by Channel Tunnel workmen near Northfleet, Kent, a year after she disappeared in April 2001.
At the time that Arlene vanished, Howard was on bail awaiting trial on rape and sex charges.
The North's Police Ombudsman, Nuala O'Loan, is investigating the police investigation into the disappearance.