Agressive ridgeback shepherd
My son and his 2 year old dog ("OB") moved from NYC to our family home on Long Island a few months ago, joining a 5 year old mix and a 6 year old lab. Things were tense at first, then seemed to relax. However, there have now been 4 occasions where OB has attacked the older dogs, seemingly for no reason. Most recently, my daughter was playing piano with the lab at her feet and OB attacked the lab leaving deep puncture wounds. My daughter was forced to physically disengage the 2 dogs, at which point the 5 year old joined the fray. It was terrifying. The dogs are all trained, and OB in particular is very smart and responsive. There are obvious triggers, like toys and food, and we have controlled those settings, but the "out of the blue" aggression leaves us all very frightened. Can you help?