The very best people you can talk to about this on P.T. are two who don't post here very often because they are so very busy. I will send them both regular emails and ask them to drop in. Mumpkees, in particular, has specialized for years in cats with disabilities that make diapers, expressing bladders and bowels, etc. necessary on a daily basis. You might also want to subscribe to the Yahoo group Handicats2, make sure it has the 2 after it because the regular Handicats group is rarely visited except by spammers.
You've done a wonderful thing and I hope this little guy has many happy years ahead of him.
Bookmarks