Great... Well your can Idea didn't work. Sif thought it was really cool and started playing with it. I've actually installed a door between the our backdoor intrance and kitchen. So now they can't get into the upstairs at all unless I'm up there to watch them. I really didn't want to "fix" the problem that way but I don't need them getting into things anymore either. We spend 90% of our time downstairs anyhow so it's not to bad.
Thanks for asking.