Penny is 2(ish) she is very well behaved when we are out of the house, her recall, drop and stay are very good and she will ignore other dogs/people. But when we are at home as soon as anyone comes up the path she barks and runs to the door, if I see them first I can get her to stay on the sofa and she just grumbles but if she notices first it's too late to stop her. As soon as the door is open she lies on her back at their feet but she sounds very vicious when she's barking. I'm not sure how to train her not to behave this way, atm Oscar just sits looking at her but i'm worried he will start doing the same. TIA :)