The four-year-old was rushed to hospital late Saturday afternoon with injuries emergency personnel had described as life-threatening.
Police earlier said the boy was five years old.
He was reportedly playing in a bedroom with other children when he fell from a window.
It was also reported the boy had been visiting family in the building and that a group of adults were socializing elsewhere in the apartment.
The president of the building's tenants association says safety locks were installed on all of the high rise's windows two years ago.
(Newstalk 1010, The Canadian Press)