What are we using for litter boxes in bug out bags

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So I have two cats and a dog, I have a bag specifically dedicated to them because some of them have medical issues so it was just easier to have a bag for them. Im mainly prepping for hurricane evacuation as I live in an area where it's really common at the moment, however while I was going through my list I realized that I do not have any type of litter box for the cats in case I have to leave and evacuate, I worry about having to transport a little box as I don't have a lot of space in my bags as it's mainly just a backpack and that's really all I have space for for free packed bags. so I was wondering what is everybody using is there a type of pop out option that like folds up or maybe have something I'm not thinking about because a lot of the things I see online are the size of regular litter boxes so I'm back at square one.