Yeah, that!If he poops and you see the string coming out, DO NOT PULL IT! Call your vet.
A needle?! Holy momma! I'm glad your kitties ok!Once my cat ate a needle attached to thread. We didn't even know until it was out the other end! Wow were we ever lucky. I think the longer the string the more dangerous it is, if it was pretty long I would be concerned. Keep an eye on your cat to make sure they aren't acting strange, and if they are take them to the vet ASAP! If they start pooping it out, I'll echo everyone else in saying do not pull it out! Instead I'd suggest cutting it every time you see some... or going to the vet.