A Montgomery County couple say a longtime Friends' Central School teacher caused permanent damage to their 5-year-old son and abused other students, and the elite private school knew about the danger the staffer posed to children, according to a newly filed lawsuit.

During the 2018-19 school year, the suit in Philadelphia Common Pleas Court alleges, the teacher repeatedly humiliated the couple’s pre-kindergarten boy in front of his classmates and repeatedly hurt him, putting her hands on his head and jerking it back and forth while reprimanding him.

After sudden behavior shifts, the boy eventually told his sister something was wrong. Eventually, he told his parents, too, and they immediately notified the school that teacher Laurie Lubking “had hurt him physically and verbally terrorized him," according to the suit filed Monday.

The boy, who is not named in the suit, told his parents he had been scared to tell them because he was afraid of getting in more trouble with his teacher.

It’s unclear whether Lubking was the subject of any investigations prior to the 2018-19 school year.

“This is shocking, nightmarish stuff for this family,” said Matt Casey, a lawyer who represents the family. “We intend to get fully to the bottom of how and why it was permitted to occur.”

Friends' Central said it does not comment on pending litigation, but spokesperson Lisa D’Orazio said, “It is our intention to defend this case vigorously.”

“The safety and well-being of our students is always Friends' Central’s top priority,” D’Orazio said in a statement.

Lubking did not return calls seeking comment.

The family is seeking unspecified damages from both Lubking and Friends' Central.

The Wynnewood school knew Lubking was a problem, the lawsuit says: While the child first told his parents he had been hurt in May 2019, the teacher had been investigated for injuring another child earlier in the school year and was allowed to return to work with children, according to the suit.

After the May incident, Lubking was removed from the classroom, the lawsuit says. When asked by administrators what happened, Lubking allegedly said the boy was “very sensitive” and probably put off by her stern tone. She said she had “bopped” the boy on the head during a game the class was playing.

“This account is untrue and appears to be an attempt to explain away any physical contact by the teacher,” the lawsuit says.

Lubking never returned to the classroom, but the school never told parents the reason for her departure, and urged the family to keep quiet about the incident, the lawsuit says.

The boy suffers lingering effects, the suit says. Prior to the incident, he was described by teachers as “sweet, kind, helpful, an admirable member of the class,” according to the suit. Now, he attends emotional support classes, requires regular therapy, is under the treatment of a psychiatrist, and has threatened to hurt himself. He has been diagnosed with post-traumatic stress disorder and other conditions, and blames his parents for failing to keep him safe, the suit says.

“This abuse has caused permanent injuries for this child that will result in a long road ahead for him and his parents,” Casey said. The child now attends another school.