Hi MeMe, welcome to our site. I'm in Ontario and I know for certain that you can have 5 children under the age of 10 (not including your own children) in your home at one time. Whether they are before or after school or full time or part time care, you can only have 5 children at one time. It's very simple. If you are unlicenced the children can be any age without restrictions but if you register with some agencies they have restrictions on the under age 2 ages.