A King County, Wash., judge dismissed charges Thursday against the boy, who has turned 14 since he allegedly stabbed his grandmother, Louise Frazier, with a kitchen knife in their home in Skyway near Seattle, the Seattle Post-Intelligencer reported. The boy must receive a psychiatric evaluation to determine if he is dangerous.

The dead woman's sister, Annette Grace of Renton, told the newspaper the boy doesn't understand what happened in March. She said he sometimes talks as if he will simply be able to return to his old life and his room in his grandmother's house.

"He's just not someone who's cognitively aware of the extent of what's taken place," Grace said. "He knows something terribly wrong has happened but the ramifications of that? No."

The boy's IQ has been found to be below 60 with some evaluators placing it in the 40s, the Post-Intelligencer said. His lawyer said he also shows signs of mental illness.