CASTLE ROCK, Colo. -- A Castle Rock mother is desperate for answers about her teenage son a year after he went missing.
Julian Revolie, 16, was last seen at his father's house in Denver on June 22, 2016.
"What is your worst fear?" asked Denver7 Reporter Jennifer Kovaleski.
"That his dad may have hurt him," said his mother Nicole Barrett.
Her son's dad, who is also named Julian Revolie, is a convicted sexually violent predator and Barrett said he turned her son into someone she didn't recognize.
"From this picture, happy -- not a worry in the world, innocent, loved animals -- to this," she said while showing photos of her son flashing gang signs. "A very evil child, teen -- I say child because he's still my child but he was completely different."
Barrett said she raised her son on her own, but decided to allow her son to meet his father for the first time when he was 15.
"It would be good for him to finally meet him and know who he was. That was the worst mistake of my life," explained Barrett.
Barrett said her ex convinced her son to stay with him, and a year later, he would disappear.
"Raising him 16 years on my own, I know my son and this is not like him," she said.
Barrett said her son is not a runaway, and she's now worried something else may have happened to him.
"I don't believe enough is being done. Something is wrong, something is very wrong," she said.
The National Center for Missing and Exploited Children is now involved and Barrett said she is not giving up hope, and has a message for her son.
"Whoever's watching, whoever's listening, even if it is my son, I love him with all my heart and I miss him and his siblings miss him," she said.
The Denver Police Department said Julian's case is still a very active and open investigation.
Anyone with information about this case or Julian's whereabouts is asked to call crime stoppers.
"The not knowing hurts more than the knowing," said Barrett.