Why can't Susie's dad find out who murdered her in The Lovely Bones?
He does know. He can't prove it. Susie's dad knows from the way George Harvey looks at him, and Harvey's manner when Susie's dad helps Harvey build the tent. One of the themes of the book is how Susie is present in spirit in her family's life--she helps her dad, Jack, to know who her killer is. Jack can't prove that Harvey is the killer, though, much to his frustration. Lindsey, Susie's sister, also knows, which is why she breaks into Harvey's house looking for evidence. But even the drawing she finds does not give the police enough evidence. Jack eventually finds the strength to let himself heal. And the way I read Harvey's death, it seemed that Susie had something to do with the icicle falling.
In the book "The Lovely Bones" Suzie's father is obsessed with finding his daughter's killer. He spends so much time obsessing that he has difficulty really focusing in on the real killer. When her father does realize her killer is the neighbor, he witnesses someone in the corn field and enters it. The people are Suzie's girlfriend and her boyfriend. The boy beats Suzie's father up. He has to have surgery on his knee cap and spends time in the hospital. Suzie wills him to be more settled and to let things go. She is aware of the damage her anger has caused her father. After he wakes up Suzie's mother has returned to him at the hospital. He decides to focus on their relationship and begin to move forward with their life.