Standing In The Shadows by Michelle Spring
Nothing is more disturbing than a child who commits murder. PI Laura Principal knows Daryll did it, but she wants to know why...11 year old Daryll Flatt killed his elderly foster mother by dropping a large concrete block from his tree house on to her head. Apparently he was angry about a lost toy, about having to get dressed up for a meeting in town. It doesn't seem like a reason to kill and Daryll's older brother Howard - consumed by Guilt that he wasn't there when Daryll needed him - has to know why the boy acted as he did. Laura principal is on the case and faced by some disturbing questions. And someone with a particular interest in the case is standing in the shadows watching her every move.