Teacher:Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.
Teacher: Now, understand the problem? Solve this instance: Originally, at the end of Nurhaci's reign, Hong Taiji got hold of the two White Banners, but after Lady Abahai's death, he switched his two banners with Dorgon and Dodo's two Yellow banners (Nurhaci gave his two Yellow Banners to the two).
Student:
Who was the brother of Hong Taiji?