Siobhan in said to be the head of the Irish coven, the other two members of her coven are her mate, Liam, and a female named Maggie. She is friends with Carlisle Cullen and comes to help his family testify against the Volturi in Breaking Dawn. She and her coven are not vegetarians, but her coven is shown to be very civilized. Though she does not think so, Carlisle believes that she has the ability to wish for outcomes and they come true. She just thinks it is good planning. She is considered a Vampire with great presence in the book, and when she talks everyone pays attention.