Who is Nikolas Cruz and What Could Have Caused Him to Kill?

The nation struggles to make sense of how another angry young man turned into a cold-blooded killer. Nikolas Cruz was adopted at birth by a middle-aged couple, Lynda and Roger Cruz, who lived on Long Island, New York. They moved to Florida for a fresh start. That's when they adopted Nikolas and his brother. Nikolas was said to be a socially awkward kid obsessed with guns. On his Instagram account, he shows off a small handgun and wields knives between his fingers.