Every July 14, the birthday of Victoria, Crown Princess of Sweden, is observed in Sweden. Although it is not a public holiday, it is an official flag day, meaning that the flag of Sweden is flown on all public buildings and poles. Crown Princess Victoria, born on July 14, 1977, is the eldest child of King Carl XVI Gustaf and is expected to ascend the throne, potentially becoming the fourth queen regnant of Sweden. She was designated as Crown Princess due to the Act of Succession passed on January 1, 1980, making her one of only three female heirs apparent in the world. As a working member of the Swedish Royal Family, she participates in various official engagements, including the Advisory Council on Foreign Affairs and celebrations for the Swedish National Day and Nobel Prize festivities. Victoria is married to Daniel Collert, and they have a daughter, Princess Estelle, Duchess of Östergötland.