In early 1942 the King arranged a four-month-long military and diplomatic mission for the Duke to the Middle East, India, and East Africa. The mission came just after Prince Henry had become a father for the first time, and it was considered a dangerous trip, as the Germans were rapidly advancing toward some of the territories the Duke would visit. The King even wrote to his sister-in-law that he would act as guardian of the newly-born Prince William if anything should happen to his brother.