Mercedes Tainot is a fictional character from the 2010 film "The Last Song," which is based on a novel by Nicholas Sparks. She is portrayed as a dedicated and caring mother who struggles with her relationship with her daughter, Ronnie Miller, played by Miley Cyrus. In the story, Mercedes is depicted as a strong woman who faces challenges while trying to reconnect with her family. Her character highlights themes of love, forgiveness, and the importance of family bonds throughout the film.