Olivia Cahill married Gideon Cahill and had five children (Madeleine was born after Gideon died). Her home was destroyed and her husband was killed in an explosion that Gideon set to stop Damien Vesper from getting his research. She was pregnant with her fifth child, Madeleine, at the time. Her four oldest children scattered, and she taught Madeleine that reuniting the family was the most important thing. In 1526. Olivia died, according to the book Vespers Rising. Olivia taught Madeleine all the skills of the other four founders. Every time Madeleine does well she uses one of these expressions to praise Madeleine:
Olivia is first shown washing the kitchen table in the garden, while watching her children fight. She is shown to disagree with Gideon's plan to give Luke, Jane, Katherine and Thomas part of the serum. She is shown to be crying after Gideon's death, and when her children left her. Damien Vesper comes and tries to steal Gideon's ring (for the Machina Fini Mundi) and Gideon's research (for himself), though Olivia manages to convince Damien Vesper to do otherwise (for now). Then she swore that her family will sit around the kitchen table (which all six ate at and forgot about fighting) again. She decides to name her daughter "Madeleine" and then she digs up Gideon's grave.
Olivia (Babbitt) is first shown after her daughter, Madeleine attacks "an old buzzard", which turns out to be her. She sees the Vespers, and she tells Madeleine that Olivia had hoped that she would never meet the Vespers, and they were lucky they avoided them for 19 years and tells Madeleine that the Vespers dosen't know she exists. She tells Madeleine to fleeand to keep her promise, and then she runs inside the building they here hiding in (O. Babbit and Daughter Apothecary) to protect the remains of Gideon's research from Damien's hands. She then dies in a fire the Vespers lit, after she refused to open the door at Damien Vesper's men command. After her death, it was revealed that she made Madeleine promise:
Gideon often thought that children have inherited their greatest qualities of Olivia. She saw love and beauty in things like minimal Jane. Katherine was able to fix anything. It could prove that Luke did as well as Thomas had enough strength and determination to break a door
Olivia was known for her intelligence, since Gideon said, in Vespers Rising, that she was much more intelligent than Damien Vesper realized. She also had a knack for acting, proved when she was able to fool Damien Vesper into believing the ring was just a token of love.