The definition of a common law spouse varies from jurisdiction to jurisdiction but in Ontario is usually considered to be in accordance with the way a ‘spouse’ is defined under Part III of the Family Law Act. Under Part III, spouses (except for married ones) are described as either “people who live together for three or more years as husband and wife”, or “People who live together in a relationship of some permanence" (and have a natural or adopted child). These two alternative types of spouses are normally included in the common perception of a ‘common law’ spouse.
The Divorce Act does not apply to common law spouses. The net effect of the Family Law Act of Ontario is to grant a system of property division to married people but not to those who are not legally married. If you are a spouse as defined under the Part III definition above, you may seek both child support and spousal support in appropriate situations.