KANSAS CITY, Mo. – A Northgate Middle School teacher resigned recently amid allegations he lured a 13-year-old female student to a treehouse for sex on multiple occasions.

KCTV5 did not name the teacher because he hasn’t yet been charged with a crime, but the child’s mother told the news site the Northgate Middle School student’s behavior changed recently and she decided to find out why.

The mother, who also was not identified to shield the alleged victim, said she combed through her daughter’s cell phone and found numerous texts between the student and former teacher that prompted her to call the police.

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“According to court documents, the teacher is accused of using Facebook and texts to tell the 13-year-old to sneak out of her grandmother’s house to meet him in a tree house to have sexual relations,” KCTV5 reports.

“He had been meeting her there every single night from midnight until 4-5 a.m.,” the mother said. “The tree house is for little kids. It is not for a 31-year-old.”

The Kansas City mother was disturbed “to find out he had picked her up and taken her to this house,” she said.

Police searched the tree house and found blankets and a pillow that appeared to have been used as a bed, and are now searching through the male teacher’s computer and cell phone for evidence, CNN reports.

“When you delete something off a phone, it is not really gone on a smartphone. You can delete it all you want, but it’s always there and they can always find it,” the mother said.

“I just don’t want it to happen to anyone else. I just want it stopped. I wish every person like that could be stopped, she said.

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The teacher resigned May 1, and the investigation is ongoing.

The teacher’s alleged sexual misconduct was met with disgust by readers online.

“I’m beginning to wonder if there are any teachers out there now days who aren’t pedophiles,” Ralph Kramden wrote.

“What is it with these pervert teachers?” commenter t posted to KCTV5. “Was becoming a teacher just a way of having sex with kids?”

“Another example of a predator most likely choosing a profession that comes with a level of trust, provides authority and allows him access to children,” Ronald added.

Others believe they know which teacher the news references, based on past experiences at the school.

“If this is the teacher I am thinking it is, my daughter alerted the counselor about him during the school year,” Sarah Jones posted. “This could have been avoided!”