"The driver stumbled out of his vehicle, too drunk to even stand, too much of an animal to even say sorry," Sage Mounsef wrote.
The family of four had been sitting at Ric's Grill at 142nd Street and 23rd Avenue for 15 minutes, she said.
"Geo impressed the waitress with his perfect manners," she said. "We ordered drinks and were simply waiting for them to arrive."
An SUV from neighbouring parking lot suddenly accelerated through the patio, pinning Geo Mounsef against a concrete wall.
"My beautiful, intelligent, funny & charming son who was at the very beginning of what was supposed to be a great life," she wrote. "The possibilities of what he could have been were literally endless and sky high."
Mounsef said the dinner out was a prize for Geo for learning to use the potty.
"Sunday morning started better than most days for Geo," she wrote. "He woke up and assembled his alphabet puzzle with mommy, while singing songs all the way through."
She wrote that Geo finally overcame his fear of the potty, "mostly out of dire need to pick from the Potty Prize Pail."
"His pride in his accomplishment set the tone for the rest of the afternoon, Mounsef wrote. "He played on his slide, and we took turns racing cars down it."
When it came for dinner the family chose Ric's Grill for the celebration.
"At that time, we didn't realize that decision would be the beginning of the end of our life."
Mounsef said she will use the Facebook site to seek justice for her son.
1st court appearance for accused
On Tuesday, Mounsef and her husband struggled to control their emotions while attending the first appearance of the man accused in their son's death.
Mounsef sobbed quietly in court as she waited for the hearing to begin.
After the hearing was delayed, she left the courtroom shouting at an articling student working for Dino Bottos, who has been hired to represent Suter.
"You make a lot of money defending baby killers," she yelled, holding a framed photo of her son. "Think of that when you put your case together. This was my son."
A police officer took the family to a private room.
Richard Suter, 62, is charged with impaired operation causing death, refusing to give a breath sample and two counts of impaired operation causing bodily harm.
A bail hearing is scheduled for Thursday. The Crown has indicated it will oppose bail.
Bottos also represented MP Peter Goldring, who was charged with refusing to give a breath sample in December 2011.
Goldring is awaiting the judge's decision following a trial in that case.
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