Tales of the Abyss
In the game "Tales of the Abyss", Princess Natalia Luzu Kimlasca-Lanvaldear died few after birth so her nanny Maggie switched her with her also newborn granddaughter, Meryl Oakland. This causes Meryl's mother Sylvia (Maggie's own daughter) to commit suicide out of grief, and her father Badaq soon became the enemy general Largo the Black Lion. Meryl, now Natalia, is raised as the Princess and doesn't find out the truth until she's a teenager.