We have found that with Pippi and Tucker that we also have to show Pippi who is the pack leader by using the dominince position. Every time she growled at Tucker or one of the others for looking at Tucker, we put her on her side, held her down and told her we were boss, not her. That seemed to actually help more than putting her in a time out.

I have no doubt this will work out. Just like bringing a new born into a home and having the older act act out, so it is with dogs. They will work it out but do remember that Joey wants attention too and you may have to let Dora know that it is Joey's turn by crating her or pushing her away. The going in the house is really the same issue - let him know it is not okay - again maybe using the dominance stance- and put him outside right away. Before long they will be best friends (okay, well at least tolerate each other).