There are still laws covering unmarried couples living together with or without children. You are not out of reach of the law changing because you are not marri

There are still laws covering unmarried couples living together with or without children. You are not out of reach of the law changing because you are not married. If you have no contract, you'll get the default anyways, its just more trouble. I don't know about where you are but there are a few different standard terms of marriage even without drafting your own custom contract. The situation is just less clear and more trouble in case things go bad if you are not married... and I don't mean divorce or separation, I also mean death, being incapacitated, stuck in a foreign country etc. And that is not even when children are involved.