If Catherine has twin girls, maybe called Margaret Anne and Bridget Rose, some godparents could be as follows: For Margaret, someone from Margaret Rose's family, such as Lord Linley or Sarah Chatto, foreign royals Mary and Frederick, Princess Anne, and from the Middletons, Michael. Bridget's godparents: (now you see my subterranean thinking) Birgitta, Duchess of Gloucester and Richard of Gloucester, Foreign royals Victoria and Daniel, Prince Harry, and from the Middletons, Carole. Bridget is a more British Isles version of Birgitta. An honor for the long service of the Gloucesters. Margaret and Bridget names go together (ending in et). One could add some more godparents but this would be a good group.