"I'm just sad and upset and I'm completely devastated this whole thing happened," said "Christine," the victim's mother.
Peterson is accused of having unlawful sex with the victim beginning last April.
"We do believe that he was grooming her prior to that when she was 16," said Katherine David, Orange County deputy district attorney.
The 48-year-old allegedly met the girl at Orange High School, where he taught Spanish for the past few years. Prosecutors say he would take her to Disneyland, meet her and her friends at social events and hang out.
"They also had each other's cell phone numbers, and so these sexually explicit text messages going back and forth is really the communication avenue that they took," said David.
"I found out through a text message and I notified Orange Police Department," said Christine.
Police arrested Peterson coming out of a riverbed in Orange, where he is suspected of regularly meeting the victim to have sex.
"She's still spiraling out of control. She's still basically brainwashed by him," said Christine.
Christine's family attorney suspects there may be other victims.
"He had known that the police were investigating him for several months and despite that fact, he still was caught with her again," said the vitcim's family attorney Vince Finaldi. "So that tells me he's very bold in what he was doing."
"Mr. Peterson is naturally very ashamed of this entire matter. Just now, his thoughts are of the students, the faculty and staff at Orange High School and hopes that his misfortune does not degrade the reputation of that very fine institution," said Peterson's attorney, Andrew Lloyd.
Peterson was free on $100,000 bail. He is expected back in court in February.
If you have information related to the case or other information involving Peterson, please call the Orange County District Attorney's Office at (714) 744-7572.