On Christmas Day 2017, 38-year-old Iris Ross was shot and killed in Phoenix, Arizona after arriving at her estranged husband’s apartment to pick up their children. Witnesses said she was shot on the front patio as she tried to flee. Her two children, 11-year-old Nigel and 10-month-old Anora, were later found dead inside the apartment.

Reports describe an hours-long barricade after the shooting. During the standoff the man in the apartment fired at police before a SWAT team entered and took him into custody. He was charged in connection with the three deaths and with multiple counts of aggravated assault. Prosecutors investigated the killings as a domestic violence incident and alleged planning following Iris’s divorce filing.

What details about that day or the people involved might help explain how this escalated into such a devastating outcome?