Introducing 2 Older dogs to New house & dog

Question
My parents have two dogs. One female beagle mix about age 9 who is the pack leader and a male Chow mix around the same age.  They just moved into my Sisters house who has a male Black Lab age 2. The lab is great with other dogs but my parents dogs are being aggressive towards the lab.  I tried to help my parents by introducing just the male dogs first.  We took them each on a leash outside the home and walked them around the block and then sat in front of the house and let them hang around each other both on leashes.  The lab is scared and the chow still wants to bite him. My dad seems to think that putting all three dogs together and "seeing how they do" will work but I know different.  Can you give me advice that I can give to my dad on how to help introduce the dogs. Thank You so much.

Answer
Letting them meet on neutral ground was a good idea.  I don't know how much it helps, but can't see how it could hurt.  Much of how well 2 dogs will get along depends on their personalities and the leadership from the owners.  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/  For more on being top dog, see http://www.dogbreedinfo.com./topdogrules.htm

The Lab could be sending signals of dominance the chow mix can't accept.  Some of this is subtle, stiff legged, leaning forward, head position, eye contact, etc.  If the dogs are given good leadership, then they are competing for lower ranks and it is less important to them.  Even so, when some dogs with an inborn high dominance drive are put together, it is difficult for even the most experienced people to keep peace.  

Are both dogs neutered?  It is no cure all, but you are fighting a losing battle not to. Do so if not already.  

Taking over as top dog will take a while.  You may not be able to leave the 2 of them together alone for a while.