The Viola Girl (Counterfeit Princess #2)
Sherri Schoenborn Murray

Princess Wren begins a journey to Yonder to see Alia, her older sister, and to say the goodbye that was never said.
Alone, and only fifteen, she has many lessons to learn, including one that costs Wren her heart.
This prodigal daughter story is filled with problems, prayers, and plenty of danger. This is BOOK TWO in the Counterfeit Princess series. It can be read as a stand-alone, but the author suggests reading The Piano Girl first.