My dogs are brothers they are 3 and 4 years old same parents different litters now the older dog will not stop humping,nipping or pulling the younger dogs fur and the younger dog is getting upset and starting to growl at the other and I do keep them separated for 2 days but does not seem to help I don't want them to start a fight cause the older dog actually belongs to my mother and is allowed to do what ever it wants to do and it is not a very obedient dog ,,were I have had my dog trainer ..PLEASE HELP ME BEFORE MY MOM AND I GET INTO AN ARGUMENT ..