Queen Elizabeth II has reigned as Queen of the United Kingdom since 1952. She was born in 1926 and became heir to the throne when her uncle abdicated in 1936. Elizabeth married Prince Philip in 1947 and they have four children. As Queen, she modernized the monarchy and carried out many international visits to promote goodwill. Her reign has also experienced challenges like family divorces and public criticism over her response to Princess Diana's death. Despite difficulties, the Queen remains dedicated to her royal duties well into her 90s.