PORT ST. LUCIE, Fla. (CBS12) — The family of a 6-year-old Fort Pierce girl killed in a go-kart crash at Urban Air Adventure Park has filed a wrongful death lawsuit alleging she was allowed to drive despite being too young and too short under the manufacturer’s safety requirements.
Steve Riddle Jr. and Brenda Horrutinier Montelie filed the lawsuit Monday as co-personal representatives of the estate of their daughter, Emma Riddle.
Emma died after a crash on Dec. 6, 2025, while attending her older sister’s birthday celebration at the Urban Air location on South U.S. Highway 1 in Port St. Lucie.
The 35-page complaint names Urban Air franchisor UATP Management, parent company Unleashed Brands, several related corporate entities and go-kart manufacturer Amusement Products as defendants. The local franchisee, NIFE Holdings, is not named as a defendant.
According to the complaint, Emma was seated behind the wheel of a two-seat go-kart, with her mother sitting beside her. Emma was 6 years old and 49 inches tall.
The family alleges the manufacturer’s operating manual required drivers of two-seat karts to be at least 18 years old and 60 inches tall. The lawsuit claims signs posted at Urban Air listed a lower height requirement and did not include the minimum driving age.
The complaint alleges an employee reopened the attraction after the regular operator had left for the night and then ran the track alone. The family claims the attraction should have had two trained workers: one to load and screen riders and another to monitor the track and operate its remote-control safety system.
Emma’s mother repeatedly tried to secure the retractable seat belts, according to the lawsuit, but the belts would not extend. The complaint alleges the ride began without either Emma or her mother being restrained and that the operator did not confirm the belts were fastened.
The operator allegedly bypassed the go-kart system’s normal starting sequence and remotely increased the karts from a slow pit speed to full speed while they remained lined up near a sharp turn.
Emma’s kart accelerated from about 3 mph to 10.8 mph, sideswiped a barrier and struck a wall at a 90-degree turn, the lawsuit alleges. The impact threw her forward into the steering wheel, causing fatal blunt-force injuries.
Emma was taken to HCA Florida Lawnwood Hospital, where she later died.
The lawsuit comes as Urban Air reviews a proposed $300,000 settlement with the Florida Department of Agriculture and Consumer Services, which regulates amusement rides in the state.
The proposed agreement would resolve an administrative case brought by the state after its investigation found multiple safety violations connected to the crash. Urban Air can accept the settlement or request a formal administrative hearing, according to the department.
State investigators determined Emma was allowed to drive the double-seat kart despite manufacturer guidelines requiring a driver to be at least 18 years old and 60 inches tall. Investigators also found neither Emma nor her mother was wearing a seat belt.
The state said the go-kart was mechanically sound, but identified several failures in how the attraction was operated. The proposed administrative settlement is separate from the family’s wrongful death lawsuit.
According to the lawsuit, state inspectors visited the attraction on Dec. 8 and Dec. 16 and cited violations involving rider age and height requirements, safety signs, seat-belt checks and operating the ride in a way that presented a risk of serious injury.
Read the lawsuit below
The complaint accuses the Urban Air corporate defendants of approving signs that conflicted with the manufacturer’s requirements, failing to establish adequate screening and staffing procedures and failing to properly train and supervise franchise employees.
It also brings product liability claims against Amusement Products, alleging defects in the seat belt and remote speed-control systems. The manufacturer is accused of failing to include safeguards that would prevent a sudden transition to full speed or keep a kart from starting when riders were not restrained.
CBS12 News previously reported that the family’s attorney said the kart had braked and accelerated erratically and failed to respond to pedal inputs before surging into the wall.
See also: $11K reward offered as manhunt for Florida murder suspect expands to Georgia, Alabama
In February, Emma’s parents were preparing legal action and had been waiting for answers. CBS12 also identified five other lawsuits involving alleged incidents at the Port St. Lucie Urban Air location in 2023 and 2024.
Those lawsuits accused the park of problems including inadequate supervision, insufficient employee training and failure to properly maintain equipment. One resulted in a settlement after a parent alleged a child was injured on a trampoline without adequate supervision.
The new lawsuit seeks damages exceeding $50,000, with the amount to be determined by a jury. The family is seeking damages under Florida’s Wrongful Death Act and has demanded a jury trial.