In 1613, she married Erik Göransson Ulfsparre af Broxvik (1577–1631), but as was the custom at the Swedish nobility up until the late 18th century, she kept her name even after her marriage.
Her spouse served as governor in Stegeborg 1615–18, Norrköping 1618–21, Kronoberg 1621–26, and Östergötland 1627–1631; Beata Oxenstierna was widowed in 1631.
Accordingly, in 1639 Ebba Leijonhufvud and Christina Natt och Dag was appointed to share the position of royal governess and foster mother with the title Upptuktelse-Förestånderska ('Castigation Mistress'), while Beata Oxenstierna and Ebba Ryning was appointed to share the position of head lady-in-waiting, all four with the formal rank and title of Hovmastarinna.
[2] The Royal Council's method of giving queen Christina several foster mothers to avoid her forming an attachment to a single person seems to have been effective: Christina dies not mention her foster mothers directly in her memoirs and does not seem to have formed any attachment to either of them, nor do they seem to have played any part at court after their term in service ended.
With some exceptions, such as Ebba Sparre, Lady Jane Ruthven and Louise van der Nooth, Christina did not show any interest in any her female courtiers whatsoever, and she generally mentions them in her memoirs only to compare herself favorably toward them by referring to herself as more masculine than them.