So my two boxers get along great, my german sheperd just stays away. We crate the little guy while we are gone and the older dogs have the run of the house. We have never had any issues with them until recently the two older dogs have been getting into the tras when we are gone. It does happen every great once in a while but now it is almost daily. We don't treat them differently, except the sheperd she's just anti-social. So are they acting out because of the pup even though we have had him for 3 months?