We had just taken in a feral mom and her litter of kittens when Gracie first came home. She was sure she was there to tell those kitten just how to behave. It seemed she was in constant motion playing with them and keeping them in line. I had the challenge of teaching her the "no barking" thing very early on since whenever she gets excited as she plays her bark becomes non-stop.
The only real problem we had was that the mom being feral did not appreciate all of Gracie's attention to her babies when they were still quite young. Gracie had to run for cover a couple of times when Mama cat decided Gracie had over stepped her bounds.
We ended up keeping a couple of the kittens and Gracie has one favorite that she still loves to play with from time to time. The cat will just lay out on the floor and Gracie will bounce around her as they dare each other to get a little closer. Sometimes the cat will get Gracie is a bear hug and they tussle for a few seconds but it's all in fun. Gracie gets all excited and barks a bit until the game comes to a draw.
Since we live outside of town in a wooded area the cats go in and out so Gracie has the job of letting me know when someone wants to come in. She takes her jobs very seriously. The cat entry job means no cat ever is allowed to wait very long since Gracie is on the alert.