We have the same problem in our household.. I'm home with Dakota all day and when hubby comes home he tries to nip at him.. I attribute this to being upset that he leaves him for hours at a time to work... I told hubby not to yell at him as this makes him worse.. What I do is take him and send him to his kennel and close the door... I don't use it as a place for him to sleep it's a punishment and relaxation room for him instead... Sometimes I do have to resort to giving him a slight slap on the butt... but he still loves me ...