One thing Jenifer Medeiros could always count on was getting a text message from her 15-year-old son, Nate Torres, whenever he went out.
The Windsor High School sophomore was true to form Saturday night when he attended a party with friends at a house near the Town Green. He sent frequent texts, including a final message at 10:30 p.m. saying he would be home soon.
"The last thing he said was, 'I love you mom,' " Medeiros said. "He always said 'I love you mom.' "
But he never came home. Around midnight, Medeiros said she got a phone call from someone who said her son had been shot at the party on Windsor Road.
She rushed to the house, getting there as police arrived, just in time to see her son being hauled away in an ambulance.
Medeiros followed the ambulance to Santa Rosa Memorial Hospital, where she waited for five hours outside the emergency room, hoping Nate would be OK.
But he wasn't. Early Sunday morning, a detective came out and told her Nate was dead, she said.
"He was my best friend," said the single mother of four boys, breaking down as she looked at pictures of Torres and his twin brother, Daniel. "I literally raised him on my own my whole life."
Investigators remained silent for a third straight day about details of the attack or a motive for the shooting, but Sonoma County Sheriff's Lt. Carlos Basurto said detectives are trying to determine whether the slaying was motivated by gang issues.
"We are investigating this as a possible gang-related homicide, but I can't get into details. We need to confirm some things," said Basurto, who is supervising the investigation.
Medeiros on Tuesday tried to make sense of what she believes to be a random act of violence that took her son's life. Family members believe the teenager was shot and killed by someone who tried to crash the party and was bounced out.
Comforted by Daniel Torres as well as her own brother and sister, she sat in her darkened Santa Rosa apartment Tuesday, bouquets of flowers and cards from well-wishers spread out on a kitchen counter. She said police had not yet interviewed her or explain what they think happened.
"It's an investigation," she said. "That's all they told me."
Basurto said 10 to 15 detectives are working on the case, many being pulled from other investigative assignments.
"We're working round the clock. This is an ongoing, hot investigation," he said, referring to active leads.
Detectives have completed interviews with people from the party and now are following leads within Sonoma County, Basurto said. He declined to reveal much more, saying investigators still are trying to determine what happened.
"I can't disclose too much… for the integrity of the case," he said.
Such killings in Windsor are rare — Sunday's slaying was the first since a man was beaten to death in 2009.
"It's always shocking when it's a juvenile," Basurto said. "It makes the guys, deep down inside, work a little bit harder when it's a kid who was killed. A lot of us have kids the same age as that boy."
Windsor Police Chief Chris Spallino also coaches the Windsor High School junior varsity football team. Torres, who just finished his freshman year at Windsor High, was a team member and would have been at practice this week.