Surviving Pack Life

Lightning is the middle child of a family of wolves. Her birth father left her mother when she was still a pup, leaving her mother to care for her and her two siblings. Less than a year after her parents split her mother remarried. As the young of another male Lightning and her siblings were unwanted in the house.
Now 18 years old, Lightning has been booted to the curb along with her younger sister. Lightning has to learn fast how to behave now that she is part of a pack, but when Kailey's first heat hits Lightning is in for a world of trouble. She now has to protect not only herself, but her sister from the large males in the pack.
Will these two girls survive life in a huge pack? Will they be able to integrate themselves into pack life as well as their brother has? Or will their unusual natures cause them to be cast out?