I Need a Title - PLEASE HELP!

I am currently working on a young adult action/adventure fantasy series that will span over seven books. It is about a young girl who is on a quest to save her dying sister.



Titles have always been my greatest weakness when it comes to storytelling. I need a name for the series and one for the first novel in it as well. I will award 10,000 gift points to the person I think has the best suggestion.



Here is what you need to know:



15-year-old female protagonist has believed in magic her whole life and she has always wanted to find it. Her younger sister has long since outgrown this fantasy and thinks older sis is crazy for still believing in it. Then one day, Protag receives a message that magic is real and where to find it. She takes younger sis along with her to prove that magic is real, but something goes terribly wrong. They find the spirit of a malevolent immortal being, which possesses the younger sister and begins killing her. Protag reaches the conclusion that if magic is killing her sister then magic can save her, so she and her brother and cousin go on a road trip to find the magic that can heal younger sis.



In the first book, Protag gets her hands on an explorer's travel log that tells of beautiful immortals and magical healing waters, and then she and company set off for the Fountain of Youth in St. Augustine, Florida. Along the way, Protag meets a gorgeous and mysterious boy who seems to be everything she wants... until he turns out to be an immortal shape-shifter who turns her into a cat. She has to outsmart him to turn back into a human and find the answers she seeks.



Throughout the series, the protagonist and her family face many dangerous, immortal adversaries and must rely on their inner strength and courage to survive. Protag remains devoted to saving her sister and will give up anything in order to do so--even her own life.



I have a few ideas for some of the names of the books in the series and they are all one word titles, but that does not mean that every title must be one world only. Please help! Thanks so much