Is there consistency in both parents setting right boundaries and limits, and sound discipline at home?
For how long has he been showing this anger issue?
People, even more children do act out what they feel, and most times anger is used as a way to relieve other feelings bothering a person, from fear to sadness. It is also true that many times children who happen to be spoiled could develop unhealthy ways of behaving and expressing their feeling and have problems getting along with others and considering their own rights and needs.
Again, core things to assess here:
1- Is there consistency in both parents parenting style-discipline?
2- Is this discipline implemented without exceptions?
3- Is this child being spoiled at home?
4- Is there any form of neglect or abuse which could be leading to real anger out of frustration?
5- Is discipline consistently implemented with adequate consequences for the child to develop sense of respect, responsibility , worthiness and caring for self and others?
6- Are there any significant marital issue which could be affecting this child, so he coudl be acting out the dysfunction in his parents' marital relationship?
many things to assess, but necessary and worthy to truly understand and take good care of this child and his anger problem.
Finally, it is parents who should take the initiative an responsibility for getting professional counseling support for parenting and coping with this anger problem.
You are doing a great job supporting them about this concern. Keep being proactive and gently pushing them to get necessary help.
Rafael Morales Toia.