Between Shades of Gray

Between Shades of Gray is partly based upon the stories Sepetys heard from survivors of the genocide of Baltic people during a visit to her relatives in Lithuania. Sepetys decided she needed to write a fiction novel rather than a non-fiction volume as a way of making it easier for survivors to talk to her. She interviewed dozens of people during her stay.

Question: is between shades of gray based on a true story
Answer: yes