About the string - we have had cats for years, and had never had this problem, but I guess we never had a string swallower before. This time, the cats were playing with a ball of string, and they seemed to be enjoying it so, I let them keep it. So stupid on my part! Our female didn't eat it, but the male did, and he does seem to be very fascinated with string, thread, ribbon, etc. I think that short pieces probably are not as much of a problem, as they might pass through, but I do not take any chances. I felt so terrible when it happened, as our cat was only a year old or so old, and he was so sick. Fortunately our vet figured out what was wrong quite quickly - of course, string did not show up on the xray... Apparently this is not an uncommon occurrence, so I try to warn people whenever they talk about their cats playing with string. And of course, you always see all those pictures of kittens/cats with a ball of yarn...