The King’s Healer Is… Five?

A person can die in one century and open their eyes in another, in a body that already belongs to someone else. That is what happens to a professor of Chinese medicine, who comes to as a five-year-old girl in an old dynasty with everything she ever learned about the body still in her head. The girl has an older sister who had worked to pay for her husband's studies. He passed his examinations, took a post, and divorced her for the imperial physician's daughter. The two sisters were taken in by an uncle and aunt who let them know daily what they cost. The professor decides she will make the man pay for what he did and make the uncle and aunt look at her sister differently. Then the emperor, out of the palace and travelling as a private man, collapses in front of her. She treats him with what she knows from her own century. He comes round and he knows who it was that treated him. In the uncle's house they start speaking to her differently.