DELPHI, Ind. (AP) — A group of family and friends gathered to release a lantern balloon on the 14th birthday of one of the two northern Indiana girls who were killed four months ago while out spending the day on a hiking trail.

The tribute Friday in Delphi for Abigail Williams came as investigators continue trying to find who killed her and 14-year-old friend Liberty German. Their bodies were found Feb. 14 in a rugged wooded area off the trail, a day after they went missing.

Anna Williams says she feels blessed by the community response since her daughter’s death and remains optimistic the slayings will be solved.

The FBI issued a renewed call for information into the deaths on Friday, asking anyone with tips to call 844-459-5786.