I agree that personality plays a huge part in this.  When Max came home from the hospital, his best friend Linda was waiting for him.  She's a very mellow dog, and Max was definitely the alpha in their relationship.  She gave his amputated area a long sniff, then gave the rest of him a good once-over as well.  This is normal, considering that your dog is going to come back with all the uncertain smells of a hospital on him.  Since most dogs end up in the vet's office or hospital sooner or later, most will recognize those smells.  That can be a little off-putting to the dog who stayed home, especially if they don't have the fondest memories of their own experiences at those places (and the average dog won't, since nothing fun ever happens at the vet).  So allow for a little adjustment period.

       As for aggression, I suppose it's possible, but I've never heard of it.  If the dogs got along before the amputation, that's not going to change afterward.  The main danger is accidental injuries.   The dog(s) who stayed behind don't know or understand what happened, so they'll try to wrestle and play with the new tripawd like they always did.  And since the new tripawd also doesn't really understand that they're missing a leg, more likely than not they'll try to play too.  That's going to lead to impacts and jolts to a sensitive area, and a lot of pain when that happens.  So for their own good, keep them from playing too hard for the first few weeks.  The sooner the wound heals, the sooner your buddies can go back to business as usual.

Well for Sammy and his crew it is complicated.  He has always wanted to be alpha, but our bigger stronger mastiff Titan took over the roll once our rottie matriarch passed on. 

So Sammy has tested and tested Titan before the whole cancer thing ever happened. They have had a couple of fights in thier life, once requiring stitches on both sides.  Since the operation I had a scary situation once, when Sammy was in pain and Titan ran over to him.  Not sure why he was so erect, hair up, tail in the dominant stance.  Sammy was in so much pain I had to get between them to make sure Titan didn't do anything inappropriate.  Someone later suggested that perhaps Titan was coming to Sammy's defense. 

My husband reads Titan better than I and has told me not to let them be alone in the yard.  Titan is feeling aggressive out there.  Titan used to not let me in the yard, until my husband put a stop to that one, so I guess it is possible he is throwing off vibes again for Sammy.  I don't sense it, but I won't take any chances.

Titan weighs about 185 lbs, Sammy weighs in at 99 lbs.  My Sheppard girl is not an issue, she gets along with everyone.

My philosophy is there is no alpha but my husband and I, and I practice that with our dogs.  I own everything, and am sharing it with them when I feel like it.  I believe the dogs still have developed their own hierarchy but it is subtle.  They do try and behave around me, because I will tell Dad!

Elizabeth and Sammy