Hello Pegn53 and welcome to the family, so glad you decided to join us and we look forward to hearing more about you and Harley Jean, what a cute name.
I'm sorry for you that Harley has chosen your sister as her favorite, but that is usually the way with a grey, they play favorites but you can still be a big part of her life. You be the one to give her the treats, that will at least put you in good graces with Harley.
It sounds like you have all the bases covered and she is adapting well to her new home and the food situation sounds like a plan to me too.
Take a little time and read thru the many threads for lots of useful information and do not hesitate to ask questions. We will do our best to get you some answers and help you in any way we can.
If you have some pictures of Harley you would like to share with us we would love to see her.