Princess Trains New Dad

On her coming-of-age day, a crown princess from an ancient dynasty has her soul transmigrate into a modern eight-year-old girl. The original child was the real daughter of a wealthy family, switched at birth, abused, and starved to death by the fake daughter. Filled with royal fury, the princess decides this father is unworthy. She finds a new, useless father everyone despises, and uses her royal wisdom to transform him into a man worth respecting.