A Toronto mother is asking the public for help after her laptop, containing thousands of photos and videos of her late children, was stolen from her parked car.

Diane Wilson was having lunch with her son at a restaurant located in the area of St. Clair Avenue and Dufferin Street over the weekend when her 15-inch MacBook Pro was stolen. An external hard drive was also taken.

Police said the theft happened on Saturday between 11:15 a.m. and 12:15 p.m. Her black, four-door 2012 Buick Verano was parked on the north side of St. Clair Avenue West.

Wilson said her laptop and hard drive contained approximately 27,000 photos and videos of two children who succumbed to a rare, degenerative disease known as late-infantile neuronal ceroid lipofuscinosis in 2003 and 2013.

"I know that whoever did take it has their own reasons for having to take it. But I really believe that they won't want to hold on to the data. It doesn't mean anything to them, but it means everything to me and to our family," Wilson said through tears on Tuesday.

"The computer would be wonderful, but the data is priceless."

Wilson was using her laptop to collect material for a book about her children's struggles and their "inspiring" fight against the rare disease.

"Our children didn’t die in vain; they died for a purpose and a lot of it is on that tape," she said.

Wilson is offering a $1,000 reward to anyone who can help track down the data that was on her laptop. She said police told her the bag that contained the laptop has since been recovered, but the computer is still missing.

Anyone with more information on the theft is asked to contact police at 416-808-1300 or Crime Stoppers anonymously at 416-222-8477 (TIPS).