OP -- as for #2 part of your post..... I would say diet too. Maybe the cat poop!!!!
Are you feeding quality kibble? Staying away from a lot of treats or letting them at the cat food? Good quality kibble, and the poop should be nice firm, dryish tootsie rolls that are easily cleaned up and don't stick to their butt or fur (unless they have the misfortune to sit on one while fresh)
