Life of Lies

Emma woke up in a hospital. She has lost her memory. She is told she fainted and thats why she can't remember anything. In the parking a little girl named Allie calls her Ella and says she is Emma's sister. Emma's parents tells her she has no sisters and the girl is probably lost. When she is changing a photo of the girl Allie and another girl falls out of her pocket. Who is the other girl? Who is Allie?