Jenni Cortez, 19, left, and Aaliyah “Tati” Granados Cortez, 16, celebrate a cousin’s Sweet 16 birthday in November in this family photo. (Photo courtesy of Wendy Cortez) A second teenage suspect was charged as an adult this week in the 2023 killing of a 16-year-old girl during what investigators believe was a robbery gone wrong in Denver’s Montbello neighborhood. Marvin Perdomo-Cil, 18, was charged Tuesday with second-degree murder, aggravated robbery and related charges in Denver District Court.