Puppy Agression

Question
Hi,  I have a 4 month old Labrador cross Boxer and a 3 month old Boarder Collie cross, they have been together since the labrador was 8 weeks old, but now for no reason at all they seem to be very aggressive with each other over everthing and nothing.  They go at each other with, and the hairs on their backs stand up.  I don't know what to do, I take the girls out, I am currently trying to get them socialised and they both have learnt to sit, come, walk on a lead etc.  Please if you have some idea as to why they are behaving like this, would you let me know.

Answer
Nobody else is answering this.  It might be best if somebody with some experience saw them to sort out aggression and rough play.  Good leadership will help if it aggression.  The key to most behavior problems is approaching things using the dog's natural instincts. 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