New puppy brought into a multi dog home

Question
Hi,
I dont really have a problem yet but I am expecting some and would like any advice you could give.

We currently have a 7yr old fixed male Aussie/Brittney mix. Great dog not so much a pack animal, much more a people animal. Has had training and really only acts up when being stubborn

We also have a 5yr old fixed female Healer/Collie mix. Great dog also has had training needs more. We call her physco dog because she is an angel 24/7 until she see's another animal she can not herd then all bets are off. However we have been working with her more and little steps in the right direction are showing. She is a aboslute alpha female.

Our 18 yr old daughter got a pup from grandma for Christmas. We are not against it we have had a 3 dog household before and really got much more joy out of it then headache. The pup she got is a 7 week old male lab/bullmastiff mix. He is adorable. He also is extremely well behaved for a pup. He has meant our 7 yr old male and our Aussie realy wants nothing to do with him. We let them work that out its only been a couple of days and we dont require the Aussie to interact. The Aussie has done nothing wrong except to warn the pup a couple of times and the smart pup listened.

Since we are away from home right now our Healer is being babysat in our home, she does not travel as well as our Aussie. Our Aussie will be back home in a few days and the daughter and pup in about 2 weeks. That will make the pup meeting the alpha female, the pack leader at about 10 weeks old. The pup will be fixed as soon as he is old enough but my concern is the 5 yr old alpha female. We have no issue treating her as an alpha and I have read everything I can on the new dog and bringing into the household. I have just never had the exp with such an "alpha " dog as our healer is. I have always had 2 or more dogs without issue but this one has me a little worried.

We really have been blessed all the dogs we have had and have have been smart and loyal and besides our female crazy dog turning into a spawn unknown to the world when she see's animals she can not herd she is a joy also. I also understand in a few years the new male pup will most likely challange the female for her Alpha role and having multi dogs in the past I am not so worried. I just dont want my Healer to harm the good but stubborn pup, because in her eyes she is the alpha and omega, any insight you might be able to share would help.

Ps there all going in for training, never hurts the old dogs to re-fresh and its something they can do together

Thank you in advance  

Answer
Likely your biggest problem will be the puppy wanting to play puppy biting games and your older dogs being well past that.  Kind of like our 12 year old Aster the grouch and the three 7 week olds we have brought into the house in the 2 years Aster have been with us.  As far as dominance goes mostly the dogs divide up as males and females.  As a male, the new puppy should allow the Heeler/Collie to be the alpha female, and largely put up with her.  

The most important thing is for all the dogs to see you as top dog.  The dogs see all the people and dogs in the household as a pack with each having their own rank in the pack and a top dog.  Life is much easier if the 2 legged pack members outrank the 4 legged ones.  You can learn to play the role of top dog by reading some books or going to a good obedience class. A good obedience class or book is about you being top dog, not about rewarding standard commands with a treat. Start at http://www.dogsbestfriend.com/