We're at whit's end with one of our cats. We have four cats. We love
them all dearly. But one cat has been more difficult than the rest and
he's almost 8 now and shows no signs of changing.

The problems started with scratching at closed doors. He hates closed
doors. So much so that he wouldn't let us sleep at night when we first
got him. He would scratch furiously at the door, non-stop for hours on
end. Nothing worked. The vacuum cleaner trick didn't work. Spray
bottle didn't work. He just kept waking us up for weeks on end. We
eventually had to put a scat mat in front of the door of our bedroom
with baby gates in order to get some peace.

That behavior hasn't abated. Just this morning he scratched on our
bathroom door incessantly as I used the restroom. I then moved to the
bedroom to stretch for the morning and he did the same thing on that
door. Can anything be done about this?

The other behavior is almost as grating. He once got up as high as
19lbs. (he's now 13lbs. after years of feeding him separately from the
girls) because we would feed all the cats at once and he would eat his
food in about 2 minutes, then move on to eating all the other cats'
food. Of course, we didn't realize the extent of how bad this was
until he'd gotten pretty big. It seemed like he was being a little
aggressive about the food, but to our discredit we weren't paying
attention for a brief period of time to what was actually happening
when they ate. Once we did it was clear what he was doing.

Now he's healthy, but he's developed a new problem. He's hungry
constantly. He tries to pull down the trash can. He jumps into the
sink every 5 minutes at night to try to lick the surface of any and
every dish in the sink. We've tried shooing him away from the sink and
counters, using a scat mat there, using a spray bottle. Nothing works.
If we leave a dish near us for more than a minute unattended he pulls
it off the table and licks it. If we leave a bowl or plate in the sink
he licks it. If we kick him out of the sink he's back in there in a
few minutes. On a given night this will happen over and over and over
and over again. We'll say his name and walk towards the sink and he'll
jump to the floor and run away. He knows he's not supposed to be doing
it, but he persists.

I don't know what to do with him. I love him, but right now I love him
a lot less. I'll never get rid of him, of course. My wife and I aren't
like that. But I don't know what to do with him. We've taken him to
the vet and had him tested for any medical condition that would cause
him to be so hungry as to do what he does. Nothing. The door thing? I
have no idea. Either way I'm losing patience with him finally and I
don't know what to do.