A man accused of killing a boy and wounding his mother and brother in an apparent road rage attack was charged with first-degree murder Thursday. Police said Jeremy Webster, 23, followed Megan Bigelow's car into a Westminster parking lot and briefly argued with her before shooting her and two of her sons point-blank June 14. Bigelow's 13-year-old son, Vaughn, was pronounced dead at the hospital following the shooting, while she and her 8-year-old son remain in critical condition.