A genealogical sketch for Maria Virginia Borghese is here. She was the daughter of Olimpia Aldobrandini.
Palazzochigiariccia.it/ipertesto/mariavirginiaborghese has a biographical sketch that Google translates to something like:
"Maria Virginia Borghese was one of the richest and wealthiest Roman noblewomen, great-niece of the Borghese Pope Paul V. On July 18, 1658 she was chosen as the bride of Agostino Chigi, nephew of the reigning Pope Alexander VII. This wedding a is very important because it marks the birth of the Roman branch of this noble family.
Mary Virginia was born in November 10, 1642 of Paul Borghese and Olimpia Aldobrandini. Her mother was sole heir of the whole rich heritage of the Aldobrandini. She bore 17 children from the marriage with Prince Agostino. The explanation for so many offspring was they had few sons, vital to the dynastic lineage. Ten daughters went to the monastic life, divided between the convents of Campansi Sienna and Montemagnanapoli Rome, while one, Constanza Chigi, was married to Prince Altieri, nephew of Pope Clement X.
The incredible riches that she brought him allowed the Chigi family to considerably increase its fortune.
Maria Virginia Borghese died in Rome on 1 March 1718."
