Cats

I am a total cat person so my husband and I got two kittens over a year and a half ago. They have become too much to handle. The cats we have are not normal. They have suddenly (six months ago) quit using their litter box among other things. We have talked to all of our family members about this (we got the kittens from my mother-in-law) and have decided they are mentally underdeveloped. They are first generation house cats and we have been told that is the problem. We can't keep them any longer but it really upsets me. I have never given any animals up before; it is until death do you part. I do not know how I will be able to part with them but I know I have to. I can't keep checking to see if my clean clothes are really clean, and pet stain remover gets expensive when you go through a bottle a week, not to mention the smell. We have worked really hard to keep out house nice but they tear everything up. We are taking them to Pets and People. They do not kill the animals; if they can't find a home for your pet they call you in a month and you get them back. I do not know what I will do if they call us to come get the cats but I almost feel worse making it another person's problem...