mary sidney was born on 27 october 1561 at tickenhill palace in the parish of bewdley, worcestershire. she was one of the seven children – three sons and four daughters – of sir henry sidney and wife mary dudley. their eldest son was sir philip sidney (1554–1586), and their second son robert sidney (1563–1626), who later became earl of leicester. as a child, she spent much time at court where her mother was a gentlewoman of the privy chamber and a close confidante of queen elizabeth i. like her brother philip, she received a humanist education which included music, needlework, and classical languages like french, italian. following the death of sidney's youngest sister, ambrosia, in 1575, the queen requested that mary to return to court to join the royal entourage.