bring out the best. >>> once again, david muir. >> reporter: sheena morris' mother gave up everythingead investigator in her daughter's case when she says no else would, determined to find answers. the boyfriend who lost his fiancÉ says, "all these years, he's been asking questions too," of the young girlfriend found in that shower. >> i ask the question all the time. i -- i asked it, "why did you do this?" i don't understand it. i mean, i -- i -- who -- who understands it? i don't. >> reporter: tonight, that team of investigators taking a second look at the case, and a florida prosecutor will decide what comes next. will there be murder charges? or will they agree with that first detective who showed up at that hotel, and found sheena in the shower, convinced it was a suicide. >> reporter: what are you hoping to hear? >> i'm hoping to hear, my phone rings, and it's the fdle, the florida department of law enforcement, and say uh "miss osborn, we have a suspect in custody." >> reporter: will this ever be over? >> when there's a trial and the jury finds the suspect guilty. that chapter