The event that's deeply seared within him
He was 16 at the time (his then girlfriend was the same age), it was his first and they were dating for 6 months or so. He had just gotten his very first driver's license (restricted though) at the time. The 3rd time he drove, a drunk driver hit them, injuring him and killing his girlfriend. Though it was said she was briefly alive for a few minutes and died in his arms.
He hasn't been acting his age since. What do you think? Can a normal person's mental growth get stunt so much after a traumatic event? At the time he was acting his age but now he's not.