Copernicus never married and is not known to have had children, but from at least 1531 until 1539 his relations with Anna Schilling, a live-in housekeeper, were seen as scandalous by two bishops of Warmia who urged him over the years to break off relations with his “mistress”. His sister Katharina married the businessman and Toruń city councilor Barthel Gertner and left five children, whom Copernicus looked after to the end of his life.
Despite being a genuinely pious Roman Catholic, Galileo fathered three children out of wedlock with Marina Gamba. They had two daughters, Virginia (born in 1600) and Livia (born in 1601), and a son, Vincenzo (born in 1606).
Because of their illegitimate birth, their father considered the girls unmarriageable, if not posing problems of prohibitively expensive support or dowries, which would have been similar to Galileo’s previous extensive financial problems with two of his sisters.
Their only worthy alternative was the religious life. Both girls were accepted by the convent of San Matteo in Arcetri and remained there for the rest of their lives.
Virginia took the name Maria Celeste upon entering the convent. She died on 2 April 1634, and is buried with Galileo at the Basilica of Santa Croce, Florence.
Livia took the name Sister Arcangela and was ill for most of her life. Vincenzo was later legitimised as the legal heir of Galileo and married Sestilia Bocchineri.