I have found that just a very soft tap tap tap on the end of their nose to get their attention and tell them, "no bite" works very well. Repetition is the key when training any animal. I have 5 kitties that I've raised from very little kittens, and they are all very well behaved, with the exception of one. (He's VERY spoiled and sprays to get attention.) All you really have to do is be sure you shower them with all the love you have to give them and they will be happy, healthy, well rounded kids! You have done a wonderful thing taking in these three wonderful babies!!! Thank you for giving them such a wonderful home!
Mary