A blend of both PS. He was the youngest and only boy. He was spoilt and enabled by My Mother who hid his petty truanting, thefts etc from my father until he was 16 and ended up doing his first stint in a young offenders institution. He was certainly 'entitled' as a youth, but I assumed it was because he was spoiled. As he entered the drug scene at approx 17, first weed, then heroin, then pills, I am not sure if this added to his disorder. He was prescribed huge doses of anti depressants and anti anxiety meds in his many jail stints and at 20 he was hit by a car and almost killed (he was not 100% a victim, he was stealing with a friend who attempted to tow a bronze statue, which fell, the car lurched and hit my brother). He was formally diagnosed shortly afterwards when he almost killed one of his wives.
So I think he was born this way, but his parenting didn't address the behaviours and then his drug abuse muddied the waters.