Shadow of the Giant
Married to a grocery store owner named Bob, Randi Firth fell in love with Achilles de Flandres, and believed he was the savior of mankind. She was the surrogate for an embryo he told her was of his seed, though in actuality it came from Petra Arkanian and Bean. Randi left Bob to have who she believed to be Achilles' son. It was her mission to raise the boy, whom she called Achilles II, to fulfill what she saw as his father's destiny, and become the ruler of Earth.
She took on a new identity as Nichelle Firth, as she had an irrational fear that Peter Wiggin and the Free People of Earth would discover her son to be Achilles' and take him away from her. She applied to be a colonist heading to the abandoned Formic worlds and eventually left Earth on a ship to Ganges.
Ender in Exile
After reaching Ganges, Randi continued to raise her son, manipulating him into hating Peter Wiggin and Bean for murdering his supposed father, Achilles.