Pesachim 9: Rava Had a Sense of Humor

NOTE: This daf deals with infant loss in a graphic way. From the mishnah, if, after you've done Bedikat Chametz, there's a weasel that brings the food from place to place, despite your search, you don't need to worry about that final transfer. This, once you've checked, you've checked, or the search would literally be never-ending. The Gemara's underlying discussion about things that are certain as compared to things that are possible veers into the discussion of miscarriage, and it's a heavy discussion that we address, and also sidestep. Also - Going back to the mishnah - as long as the weasel tracked the chametz through the house on the 13th of Nisan, and not after the bedikah on the 14th, there should be no issue. But how can that be a certainty? Note that the weasel represents any way that chametz may move in your home without your knowledge.