What age does an infant show anger?

i think an infant shows anger at a very very early stage that is during the first three months. when he/she is hungry and there is a delay in presenting the breast ,there is a clear loud high pitch scream indicating 'anger'

Toddler's terrible twos are quite well known,which become compounded if a sibling shows up.Statements such as',When can we send the baby back?'are amusing to the adults but quite serious for the toddler.

how does this thinking process consolidates in to a viciously violent behaviors of a spouse