Young child with post traumatic stress disorder

Please help. A four year old boy I know suffered an abduction and violent assault 12 months ago. He has not been the same since. Symptoms I'd noticed the day after the incident, continue to persist a year later. They are - the pupils in his eyes seem smaller and somehow harder - sometimes he looks psychotic, he was previously a very gentle, happy child. He points his finger A LOT. His index finger is almost always in a pointing position, tracing invisible circles in the air. He counts numbers persistently. He says opposites all the time and reverses things - for example "good is bad", "bad is good". When he gets upset he talks about cutting heads off, knifes, axes, cutting things into pieces. He hides. He wants to watch scary things. He had a fixation with cats but that has passed. His post traumatic stress was extreme in the months after the attack, some of his hair turned white. Mostly he is better and back to normal now but he still seems to me to be carrying a "hard look" in his eyes, with tiny pupils - though not all the time. When he says violent things it's almost scary. I know he is different from the child he was before the attack. He is a lovely child otherwise and it is only the effects of the attack that have created these symptoms. He is extremely intelligent, perceptive and sensitive, loves music and dancing, good sense of humour, exceptionally good with words, prone to asthma type coughs and eczema. Contrary to these symptoms he is very loving and affectionate. Is there anything that can help these symptoms go away, except perhaps more time? Thanks.