A problem with this film
Performances great all around, very suspenseful, but...
Joey is telling his version of events to Bobby, the neighbor girl
and in this version of events we see his sister Suzie fall into the tub
and hit her head. This would break the rule of point of view. When Nanny comes home and accidentally drowns his sister, if he knew she was lying at the bottom of the tub, wouldn't this point to his guilt? It simply breaks a rule of film-making/story-telling.
When Nanny tells her story it is completely by the book from her point of view.
Nanny's real crime is that she left the children alone. When she comes back and accidentally kills Suzie, her guilt over her daughter's own death by illegal abortion causes momentary psychosis and she begins washing Suzie's dead body, talking to her as if alive. Joey sees her, goes to report her, but obviously Nanny reports him, saying it was all his fault.