Mark of an Angel (2008)

Divorced mum Elsa Valentin (Catherine Frot) is battling for custody of her son and juggling her job at a pharmacy. Her life is turned upside down when she crosses paths with Lola, a young girl whom she believes to be the daughter she lost six years previous in a hospital fire. Unable to let her thoughts go, Elsa first stalks and then shrewdly befriends Lolas mum Claire (Sandrine Bonnaire) inching her way into Lolas life, at the expense of her own son and to the bewilderment of her parents. As Elsas obsession heightens and her behaviour becomes increasingly disturbing, Claire confronts Elsa, which in turn brings deeply buried secrets to the surface.