"Runaway Twin" is a children's novel by Peg Kehret, first published in 2005. The story follows 12-year-old Sunny Skyland, who was separated from her twin sister, Starr, at birth and has been living in foster care for most of her life. When Sunny learns about Starr's existence, she sets out on a journey to find her. With the help of a kind truck driver, Sunny travels across the country, facing many challenges and dangers along the way. As she gets closer to finding Starr, Sunny discovers secrets about her past and her family that she never could have imagined. The novel explores themes of identity, family, and perseverance. It has been praised for its fast-paced plot, relatable characters, and themes that resonate with young readers.