There are many gaps in this story but more importantly, this is a person struggling with a mental condition who shouldn't be paraded as a news piece until he recovers, or at least, gets to the point where psychiatrists rule out any further improvements.
Eric Erikson said that a child's social and emotional development is shaped by relationships/environment in which they grow.
The behaviour of Monkeys were his primary social environment.
It also relates to social learning theory (Albert Bandura) & attachment theory (John Bowlby)