The rules for distribution of estates with no wills in Ontario are fixed, and often very harsh.

Zero to common law spouses: not legally married, no inheritance;
If married and no issue, 100% to the spouse;

If married and children, the first $200,000 and then a percentage (either 1/2 or 1/3) to the spouse, the balance to the child(ren) equally per stirpes;

If no spouse, but children, then to the children per stirpes;

If no spouse and no issue, then 100% to parents equally;

If no spouse, no issue and no parents, then 100% to siblings per stirpes;

If no spouse, no issue, no parents and no siblings, then 100% to nephews and nieces;

If no spouse, no children, no parents and no siblings, no nephews or nieces, then 100% to the surviving closest level of kin by blood.

If no surviving kin by blood, to the Ontario government.
Subject to claims of someone who is financially dependent on the deceased person