Ontario law compels people to take care of their dependants. Even death does not relieve that obligation: a person is required by law to make provisions through their estate for people who depend on them. These include provisions for common-law spouses, same sex partners, parents, children, grandchildren, and siblings.
If you are dependent on someone who passes away, they must make sure that you are provided for adequately. If that’s not done, you may make a claim against the estate. Like most claims, these claims must be made promptly as they are subject to a limitation period.