I am a provider in Ontario. You are allowed 5 who are NOT related to you. I can have 5 kids of my own and then take care of 5 and it is perfectly legal. Also you are incorrect in stating the ages that you are allowed. If you are a private home daycare you can have five 6 month old babies if you wanted to and that is also perfectly legal.
I know the laws in Alberta are different as I have a friend who actually does have 5 kids of her own and does daycare as well and she explained it all to me before, but I forget what the different rules are.