Cäcilia Cordula Stamm (née Stamm; 23 October 1727 – 22 August 1793) was the mother of Constanze Weber and the mother-in-law of Wolfgang Amadeus Mozart. She was born in Mannheim, the daughter of Johann Otto Stamm, a government secretary, and Sophia Elisabeth Wimmer. She married (1733–1779) on 14 September 1756, and had four daughters: Josepha, Aloysia, Constanze, and Sophie. Constanze was the only one who did not become a professional singer, but, according to Mozart, she possessed a fine voice and musical ear. The children were born in Zell im Wiesental, but the family moved to Mannheim soon after Sophie was born.