Cecilia was born on November 16th, 1540. Cecilia's father was Gustav I Vasa and her mother was Margareta Lejonhufvud. Her paternal grandparents were Erik Vasa and Cecilia Eka. She had two brothers and two sisters, named Johann III, Karl IX, Catharina and Elisabet. She was the third oldest of the five children. She had a half-brother named Erik XIV. She died at the age of 86 on January 27th, 1627.