What is it?

It's always happy.
But it's not Michael Owen.

Its naps are never long enough.
But it isn't a three-year-old.

It likes cats.
But it's not an old lady.

It's mangy.
But it's not a mutt.

It looks like a grizzly bear.
But it's faking.

It still smells even after a bath.
And it wants to come inside and sit in your lap.

It's Lucy!