Who stole Sadie and replaced her with an exact copy?

Tuesday morning I was in the family room awaiting my Tuesday lunch date when Sadie came down.  She's pretty reclusive, when we're all in the family room (Carl, Sassy and I), Sadie is usually in the back bedroom or our bedroom upstairs.  We've not been able to convince her to hang with us.  But Tuesday, there she was.  So I grabbed the stick with the flannel strip and tried to entice her to play...and she did.  I had her running all over the family room while Sassy watched with what I imagine was astonishment.  We played Wednesday and again today.  So, either the pod people have been here, cloned Sadie, took away the real one and left a pliant duplicate -- or Sadie is coming around.