Oh, yes, they are definately supervised at all times..in fact, when they are together, Boomer is always on his lead so we can control how close and friendly he gets.....we sort of take Cassie's lead...if she snaps immediately, we know she wants no part of him at the moment. There are some times when she will tolerate him standing next to her or even sniffing her. She has actually wagged her tail, so in these instances we try to really encourage her and brag on her behavior while at the same time telling Boomer to "be nice".Thanks again for everyone's help!