CHICAGO (CBS) – A Wilmington couple is suing a southwest suburban school district because their 10-year-old daughter was humiliated on a field trip last January when teachers allegedly refused to stop for a bathroom break and forced her to urinate in a cup on a moving school bus.

Todd and Lisa Holmes filed the emotional distress lawsuit Tuesday against Wilmington School District 209U, Supt. Jay Plese and Wilmington Middle School, among others.

“Obviously the parents are very distraught and upset that this happened,” said the family’s attorney, Telly Nakos. “They entrust the parents and the teachers and the chaperones on the field trip to provide a safe environment for the children and what occurred was just outrageous.”

Nakos said teachers shielded the 10-year-old girl with coats as she urinated into a cup in the front stairs of the bus, while it was still driving down the road.

A group of middle-school boys and girls were aboard the bus, returning from a Jan. 10, 2012, field trip to a Chicago Wolves hockey game, according to Nakos and the lawsuit.

The girl had asked multiple times to stop the bus so she could use the restroom, Nakos said. The bus driver contacted a dispatcher and asked to stop, but was denied. But the bus later pulled over so the girl could throw out the contents of the cup.

The lawsuit claims the girl — who is named only as Jane Doe — was left humiliated and suffered extreme emotional distress from the incident.

The Wilmington School District has not been served with the suit and declined to comment because the matter involves a child. They have contacted their insurance company, a spokesperson said.

“They are very serious about having the school district and the bus company face up to their responsibilities,” Nakos said. “When parents entrust their children to the school this type of conduct is unimaginable.”

The Southern Will County Cooperative for Special Education and one of its employees are also named as defendants because they were part of the trip, but the girl is not a special needs student, Nakos said.

Two Wilmington Middle School teachers who were aboard the bus are also being sued, as is Illinois Central School Bus, its bus driver and its radio bus dispatcher.

The bus company and the special education cooperative did not return messages seeking comment.

The suit, filed in Cook County Circuit Court, claims three counts of emotional distress and seeks more than $150,000 in damages.

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