My family has an almost-11-month old puppy, a cocker spaniel/Jack Russel cross. She is very lovable, sweet and friendly however she does do destructive things such as attacking the cat, digging, ripping up things and stealing food from tables. She goes for at least two walks a day, sometimes three and is quite good on the lead, occasionally she pulls. She is on the Hill's Science diet, sometimes she gets very hyper when visitors arrive and she starts jumping all over them. The only person she really respects is my father and he has been away for two weeks so her behaviour has been getting worse gradually. She won't listen to anyone else when we try get back something she has stolen (like a pen off the table) and often starts chewing things, sometimes even eating them. A dog trainer has been to train her, it works wonderfully for awhile but then wears off. Can anyone give any advice as to how we should train her? EDIT: She is spade and up to date with vaccinations.