<a href="mailto: dvsavini@cbs.com; mhlebeau@cbs.com; mayoungerman@cbs.com" target="_blank">Send Your Tips To Dave Savini</a>By Dave Savini

(CBS) –– Security cameras and GPS systems on school buses are not required in Illinois, but many school districts have installed them in order to protect children.

One family is speaking out after they claim the unthinkable happened to their twin daughters.

The mother and father of twin 3-year-old daughters want to keep their names private — but not their battle.

They’re fighting to protect other children from what a school bus driver allegedly did to their daughters in January.

“Every time I see a school bus I panic because I don’t know how many other kids this has happened to,” the Willowbrook mother says tearfully.

The bus driver worked for Grand Prairie Transit, which has a contract to provide transportation for special education students in 16 school districts in the western suburbs. The districts include Gower Middle School, where the children were enrolled.

Guerrero declined comment. But officials for Grand Prairie Transit confirmed he was fired after a state investigation revealed this month there is “credible evidence of child abuse and/or neglect.”

The family says the bus driver allegedly changed his route so that their daughters would be his last stop of the day. They say that gave him time to be alone with them.

“It just seems that their innocence has been taken from them at the age of 3,” the girls’ father says.

The twins were attending Gower in Burr Ridge for speech therapy, but because they were too little to board without assistance they didn’t get to ride on regular Gower School District 62 buses, which all have video cameras.

Instead, they ended up on a Grand Prairie bus, a third-party contractor, which had no security camera aboard.

A Grand Prairie manager declined comment as to why the company didn’t install cameras.

“We had a system failure here,” says Tony Romanucci, who is the attorney representing the family and the twin girls.

Romanucci also believes the company should have had a GPS on the bus to see if the driver went off-route.

Sheri Wernsing runs LADSE, the Lagrange Area Department of Special Education, which hired Grand Prairie. She confirms cameras were installed this spring after the alleged abuse.

LADSE gets federal, state and local funds to provide special education services, including transit for their 16 member districts. Wernsing says there was not a contractual requirement for cameras on Grand Prairie buses until after the incident.

Now the parents of the twin girls who were allegedly abused want a state law making cameras and GPS systems mandatory on all buses.

The family has filed suit against the school district, the bus company, Guerrero and LADSE.

The family says they hope police pursue the case now that the DCFS investigation revealed there was credible evidence that abuse occurred.