If "Sir Gaalad" refers to a character in a particular story, myth, or cultural context, the purpose of supernatural occurrences when he is present would depend on the narrative or mythology surrounding that character. In many stories, supernatural events or elements are often used to highlight the extraordinary nature of a character, convey a sense of destiny or magical influence, or drive the plot forward.
If you have a specific reference or context for "Sir Gaalad," I recommend checking the source material, such as a book, movie, or other media, for more information about the character and the purpose of supernatural occurrences in their presence. If "Sir Gaalad" is from a work of fiction, understanding the author's intentions and the broader context of the story would provide insights into the significance of supernatural elements in relation to the character.