We have got a brother and sister Chug's (Chihuahua and Pug mix) and the female is constantly chasing her tail and her brother starts barking at her then the fight is on. We often get bit when breaking them up. They also go nuts when anyone comesover. We have to put them in another room and the tail chasing and fighting sometimes starts. When the grandchildren come they go nuts for a little while then settle down. How do I get them to stop this? The female seems to be hard headed and still wants to run out the front door and around yard and sometimes into highway before we can corner her. She also really wants to get upset when we wake and move her. They were both victims of disfunctional familys, they were passed around a couple of familys. Their mother died when they were two days old and we got the female at 5 weeks and the male at 7 weeks and she is hardon him and sometimes wont let him eat or finishes hers and nudges him away from his bowl. She is way smaller and has more chihuahua in her and her brother seems to have more pug. You can't not love 'em cause they are otherwise so sweet and cute!!They seem to do well with sit and working on stay, love to play ball and do drop fair. But she is the queen and he never get's to bring it back unless she's not around. We are always home with them and rarely leave them alone. They get mad then and try to chew up the wooden objects and baseboards, any paper is everywhere in bits. We also have a wild cat (not a wildcat!)that they play with and all 3 of them lay real close and sun! And they are 8 months old now. Any ideas?