I think one of our toilets is backing up into our basement's toilet. What could be going on? Is it something that I can fix. I have 2 children, is it dangerous?

Your main sewer line is blocked past the basement toilet. Call drain cleaning contractor to snake you main sewer line. Do you have a clean out in front of your house?

Every sewage spill is dangerous. Not only to you and your children but to anybody around. You should correct this problem ASAP.

Good luck... Let us know how you did... Milo