I have an 11 year old boy ,who loses his temper all the time ,he is constantlly angry with everyone

I have another son who I have brought up in exactly the same way who is pleasant,placid and calm ,he is 15 and they are like chalk and cheese ,

Has your son ever seen a doctor for his anger? Has he ever been diagnosed with any mental problems? Does he take any medications? Were there any difficult events in his life that he may have issues with? (for example, divorce, abuse at school, bullying, etc.)
Does he have any medical conditions? Have you tried counseling? What are his dietary/exercise habits? Has he ever been violent towards you or anyone else?