Melanie Laforest organized the birthday party, down to the festive decorations, in the hopes of drawing the attention of city officials.
Laforest told CBC that the gaping hole, situated at the corner of 10th Avenue and Holt Street, is right in front of her daycare — and had been there for about a year.
The hole was covered with two large metal plates and surrounded by orange pylons.
In a written statement issued last week, the borough said the hole had only been there since February.
It said repairs, which include fixing pipes underground, would be carried out within the week.