I had a bullying problem with Biba when i got Lola..Biba bullied Lola... to the point that Lola would eventually retaliate after giving Biba all the submissive/give up signs which Biba ignored
...i do think bully dogs pick on the weakest dog as Biba would never bully another dog outside of the house...she is actually quite fearful of other dogs which i think added to the problem at home..as in it made her feel in control to bully Lola
...she no longer bullies Lola...the main reason i feel is that Lola is now bigger and stronger than her so she is physically unable to do it anymore
but i did have a behaviourist out as i thought if i handled it wrongly it would turn into a long term problem
ie:2 bitches not getting on is not a good long term outlook
she would also bully her on walks and would chase her down until she got hold of her
...i would give Biba a warning of "enough"and if she persisted she would be put back on the lead...i sometimes had to chase
her around the field to catch her but i always made sure i followed through ...how ever long it took...it was a long slow process aided by the fact that Lola was eventually able to out run Biba...so Biba gave up chasing her
Not sure if what i was told to do would be any good for a pup as Biba was alot older than that ...could be worth talking to someone with knowledge in dog behaviour