Sounds like schizophrenia which tends to surface in men in their late teens-early 20s. His family probably saw signs but were in denial.
I wonder.
From his blogspot: I consider myself a sophisticated, polite gentleman, unlike most boys my age. My father is of British descent, and my mother is of Asian descent, so that makes me a Eurasian. I enjoy hiking, exercising, watching sunsets, traveling, cars, fashion, going to nice restaurants, and going to parties. I have traveled all over the world, ever since I was a child. So far, I have visited ten countries, including Great Britain, the United States, France, Spain, Greece, Germany, Mexico, Singapore, Malaysia, and Morocco.
The father’s wife is from Morocco. Not sure if it is the shooters mother or step-mother though