Introducing a ShihTzu Pup to 2 Adult male Westies??

Calibos

Bit of Background.

We have 2 Neutered four year old Westie Brothers called Butch and Sundance. Other than the occasional Mexican standoff that dissipates back to wagging tails after a few moments, they have only had 3 full on fights in their whole lives 2 of which were within days of each other before they reached 1yo. The third fight was about a fortnight ago when butch stumbled upon Sundances' pizza crust stash in the back garden. None of the fights resulted in blood being drawn and all the fights were over in seconds. Bloody intense and loud few seconds though!

They are strange in that both exhibit different dominent behaviours. Sunny seems to wait till Butch has eaten most of his grub before he starts his but will finish off anything butch leaves if butches back is turned. Even if Butch catches him in the act Butch will do nothing. Butch is the pig btw whose weight has to be watched, Sunny is lean. Both get fed the same amount.

Butch will barge out the door first even if Sunny is in front of him. Sunny will generally get out of his way but occasionally gets frustrated at Butches impertinance and will nip at butches heals. So Butch eats first and gets out the door first but any contact with another dog and Butch is the submissive one with the slow slinking away from the other dog trying to sniff with his head down and tail down. Sunny on the other hand is cocky and if the other dog persists with the sniffing more than he would like will grumble a warning or in more intense situations mock charge with accompanying barking.

Neither dog has ever attacked another dog but Sunny will not hesitate to let the other dog know he has had enough.

One time I had them out on the lead when the local pair of Red Setters which are the bane of every dogs life in the estate came charging around the corner off the lead. Garda Owner lets them off the lead in the estate a few times a week and is always a few hundred feet behind!! Asshole!! Anyway they charge over to my two dogs. The dominant Red Setter starts growling and baring his teeth straight away. I start ****ting myself, Butch hides behind my legs and Sunny...........lets out a battle bark and launches himself all teeth, and claws at the red setter about 6 times his size. The 2 red Setters got the fright of their lives and hastily retreated back off up the road.:D

On the subject of Pack hierarchy and do's and don'ts, both dogs can alternate sitting on the back of the couch higher than the rest of us without showing dominence or aggression to each other or any of the family. They remain submissive to the rest of the family and to me the Alpha. I know its wrong to let a dog sit higher than you but it hasn't seemed to give either dog ideas above their station. Both sleep on the end of my bed alongside each other without any possesiveness or signs of aggression, dominence over each other or me. Looks like they read the Dominance/Pack rule book and chewed it up and spat it out.

Anyway background info complete...... we just got a female Shih-Tzu 10wo puppy called Cassidy about 3 days ago. The Westies didn't know what to make of her and would leave the room and hide for the first day. On the second day they didn't mind being in the same room as her as long as it looked like we had control of her or she was asleep. If she got up and headed in their direction they would scarper out of the room again. Yesterday when we had her on the floor and she made a move for Sunny he gave a warning grumble. We picked her up straight away. Today we tried coaxing him to come over for a sniff. Tentatively he approaced and when she got up to move over to him with her puppy enthusiasm he bared his teeth, full on growl and snapped at her pushing her down with his paw. She whelped and rolled over exposing her belly which Sunny duly sniffed.

We put her back in her cage and she started jumping at the bars and barking. I went over and sunny followed. He let out some warning grumbles and she would stop barking and act submissive.

I had hoped that maybe Sunny had established that she was no threat to him and that he had established dominance and would start to mellow out. Maybe I'm hoping for too much and its much to soon. Anyway tonight the brother had the pup out the back garden playing chasing. Sunny and Butch have seemed disinterested with this activity up till now but tonight they went ape**** at the patio door! Jealousy?? Thinking the pup chasing the brother(Adult) was attacking him??

We have been giving the 2 westies more attention than ever btw and feeding them first and except the odd time when she is in someones arms, always having her at a lower level then the lads.

Should I continue to allow situations were she might go to Sunny in her puppy inoccence and let him growl and even bare teeth and lunge at her (So he can establish his dominance?)or should I intervene even before then and give out to him. I mean I am right there for these situations to stop it getting massively out of hand but I am just not sure here the line is drawn in letting him show her who's boss. Should I be letting any of this develop and at the first grumble/growl be showing Sunny that I am the boss and this pup is under my protection?ie. Am I letting things go too far or not far enough?

Really don't know what to do exactly in this situation as we never got another dog while the previous dogs were still alive. The Westies were the first time we had two dogs at the same time but it was a less tense situation seeing as it was puppy against puppy rather than Puppy against adult dog. Never had to introduce a new dog to dogs already in the household before.

Sorry about the long post btw but hopefully I have given enough detail that you lot might be able to give me some hint's, tips, guidance etc.