King Charles has returned to public duties after he was hospitalized for temporary side effects from his ongoing cancer treatment. On Tuesday, the monarch appeared in good spirits as he stepped out to attend an investiture ceremony held at Windsor Castle.

The Palace didn't tell Prince Harry about King Charles' hospitalization, and instead he had to hear on the news—here's why.

King Charles might have been hospitalized last week, but he showed no signs of slowing down on Tuesday, April 1 as he returned to royal duties. The King—who was briefly kept in the hospital after suffering side effects from cancer treatment—was forced to cancel his planned engagements on March 27 and 28,