cool!
Have u tried clicker trainign with him. It just occured to me that if he is a GSD collie cross I expect that he is very intelligent. I would definately advise the book above. It is great.
Below is a link from youtube. It shows a video of Mary Ray- the person who wrote it and what she has taught her dogs using clicker training ( the method used in the book). My dog was clicker trained right as a pup but I think that it would be an excellent thing for you to start with sunny to give him some mental stimulation and to allow him to bond even more with you and your family
YouTube - Mary Ray and her dancing dogs perform on The Underdog Show
YouTube - Mary Ray Cruft 2007

__________________