Actually Jamie & Max is owne by me! not my sister! so i dun think she knows how to answer ur question!
Jamie (GSD) is elder than Max(GR) 9 months, she likes to bully him but Max sure will fight back than she'll run away! although they likes to bite each other, but they wont hurt themselves. coz, my GSD is gentle than my GR he plays rough!
so from wut my experience is GSD will accept anyone or new four legg member to the family very well and the most important thing is how the owner interact them to each other! hope this helps!
anyway, if u wish to chat more about my dogs, u can always reach me on msn msg.