Two Montreal sisters believe their invention could save the lives of children inadvertently left in the back of sweltering cars.

Marie-Pier Vermette-Lacroix and her twin sister Sophie have created sensored cushions, designed to sit under the seats of the driver and baby, which are connected by wires.

An alarm sounds within seconds if only the baby is seated.

“The goal is to save the life of the baby,” said Marie-Pier.

The girls revealed they’ve worked more than 100 hours on the project.

“We worked all last year during the school time,” Marie-Pier added. “We worked during our vacation for Christmas and the March break.”

And the device recently got a mention in a coroner's report into the 2016 death of an infant left in the back of a car in Saint-Jérôme, Que.

The coroner questioned why technology isn’t being used to stop these kinds of deaths.

The sisters appreciated the support.

“It motivates us to continue to upgrade the project,” Sophie said. “It’s also touching because the coroner said that. It’s very nice.”

The twins have already made plans on how to improve their device further, by removing the wires between the two seats and adding a Bluetooth system.

Just two weeks ago a child died in Montreal after being left in a hot car.

The tot’s father forgot to drop off his six-month-old son at a daycare and found the baby’s body in his vehicle after work.