Ouch! I'm so sorry. I also am sorry to say this is pretty serious and an indication of something wrong. How old is he now? Is he in school? Perhaps your daughter could have a talk with people at the school about any behaviour they have witnessed and/or having him see a school psychologist (pretty much all school boards will have one). She should also mention this to the family doctor. If he feels it is warranted he could also start the ball rolling with getting an assessment for the boy. At the same time, by talking with an outside party, it may be determined why the boy feels this way.