HOUSTON, Texas (KTRK) -- A Houston psychiatrist says the new generation of parents is responsible for closely watching their children's lives in two worlds: reality and cyber.
"Having your kids' secret codes and passwords, so you can go where they go," said Dr. Richard Pesikoff.
The message comes after Lamar High School senior Delindsey Mack was gunned down outside the campus last week. His parents now blame the teen's Instagram activity.
RELATED: Father of slain Lamar HS student says son's social media profile contributed to murder
"We have discovered that Delindsey had an alternative persona, it wasn't even an alternative life, it was an alternative persona where he presented himself to be something that anybody who knew him knew he was not," said Dr. D. Z. Cofield, pastor at Good Hope Missionary Baptist Church.
The pastor joined Delindsey's father for a media briefing Monday. They tell us the 18-year-old's Instagram account and his real life were nothing alike.
At home, he was a well-mannered teen, involved with his family's church and focused on getting his high school diploma. Online, he posted pictures with guns and money.
SEE MORE: 18-year-old killed and 15-year-old grazed by bullet identified as Lamar HS students
His pastor says none of that was real.
"One family member called him a 'bedroom gangster,' because that's what it was," Cofield said. "He's in his room, creating this persona and sending out direct messages with people and commenting on things that are happening in the community, and it cost him his life."
Houston police are still investigating Delindsey's death, telling Eyewitness News it is gang related, and the victim appears to have been targeted.
The HPD Gang Unit is assisting homicide detectives.
RELATED: Family speaks out about Delindsey Mack's shocking murder outside Lamar High School
Dr. Pesikoff says children and teens, even as old as 18 or 19, must be monitored online because their brains simply are not mature enough to always make the right decision.
"The prefrontal lobe, the part of the brain that helps you make a judgement, good, bad, terrible, terrific, isn't finished growing," said Pesikoff.
"We're literally putting technological guns in the hands of our children when we give them access to the entire world and they don't have the maturity to handle it," said Pastor Cofield.
SEE ALSO: Lamar High School parents demand tighter security after student's fatal shooting
Delindsey's family says the teen used his father's gun for several of the Instagram photos and also cash from the family business.
"Social media may not be your thing, but you better make it your thing, because that's the way and that's the world your child lives in," said Cofield said.
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