Barking at the mailman

Since Oliver & Lady are up at the cabin with my mother, Princess gets to attack the mail all on her own. The funny thing is she was knocked out on the couch when the mail man pushed the mail through the slot. So, once she heard the door closed, she jumped off and started barking letting the mail man know she will get him next time. She has such a deep bark for a 23 pound dog but it goes with her tough muscle body of hers.