MADONNA surprised CAMILLA, Duchess of Cornwall when she phoned to tell the British royal they are distantly related. The 47-year-old HUNG UP hitmaker - who has also discovered blood-links with Canadian singer CELINE DION - is urging her 'relations' to join her and genealogist William Addams Reitwiesner in their quest to trace their entire family tree. Reitwiesner explains, "Camilla and Madonna are both descended from Zacharie Cloutier, who lived from 1617 to 1708. And Camilla and Celine descend from Jean Guyon, who lived from 1617 to 1708. "Both Jean and Zacharie died in Chateau-Richer, Quebec. Because of their unusual French-Canadian ancestry, they are all blood relations. Madonna is absolutely fascinated by this."