Thanks for the replies, I could understand Tilly trying to take advantage of Smarties age (not that she shows her age at all - still thinks she's a puppy) but Tilly was already top dog to begin with. They never fight over food or bones, it happened the first time when they were play fighting - which they do all the time with usually no problem and the second time me and my friend were messing about and went running from my garden into my house, the dogs got all excited and the next minute were having a full on brawl