Matthew Nicholson lived in Modesto, California, a city some 75 miles east of San Francisco.
Nicholson reportedly fired two shots into a wall, and then shot Lydia in the head.
A man in Ceres (Stanislaus County) allegedly shot and killed his mother after an argument while playing video games.
During their investigation, police determined 28-year-old Matthew Nicholson had been in his bedroom playing video games when he became upset and started yelling.
Immediately after the son left, Loren Nicholson phoned into the police to report the incident where Lydia was then rushed to the hospital before passing from injury.
At the point when the mother went to mind him, Matthew Nicholson contended with her and broke his own particular headset. According to a family friend, Loren immediately grabbed the gun and emptied it and called the police. Nicholson then ran out and began driving to a relative's home in Riverbank.
Matthew Nicholson, 28, is seen in a booking photo released January 12, 2018, by the Ceres Police Department.
After retreating to his room, Lydia Nicholson reportedly attempted to check on him, resulting in a re-ignition of the earlier argument and another shouting match, police reports indicate.
Nicholson worked at Christine Sipherd Elementary School in Modesto, but left previous year, Jamie Trevino, who says her kids go to the school, said in a Facebook comment.
Police reportedly apprehended the man from Ceres Matthew Nicholson, aged 28, late Thursday for charges of homicide.
People with information about the case are asked to contact Det.