When did the duchess, who was married to philippe, die?
CREATE TABLE "house_of_savoy" (
  "name" text,
  "father" text,
  "birth" text,
  "marriage" text,
  "became_duchess" text,
  "ceased_to_be_duchess" text,
  "death" text,
  "spouse" text
);
SELECT "death" FROM "house_of_savoy" WHERE "spouse"='philippe';