"The fact that you are so concerned about doing so increases the odds that you will not" Hannibal reassured him, noticing how deep-rooted these fears were. Intrinsically linked with his family, particularly his mother and brother.
"We are all prone to 'fly off the handle' now and then. If you feel yourself becoming angry, send them to another room until you are calm enough to deal with the situation rationally" the Doctor suggested, it would result in a better suited punishment and alleviate such feelings of guilt.