The mother of 3Jane and wife to John Ashpool is one sad story. Her husband strangled her to death before the events of the novel, but her presence is felt throughout. After all, she's the one who helped make the Tessier-Ashpool name into a financial powerhouse.
She also began overseeing the formation of the AIs Wintermute and Neuromancer. Her goal was to create a "symbiotic relationship with the AI's" one where the "Tessier-Ashpool would be immortal, a hive, each of us units of a larger entity" (19.39). What exactly that entails and why she kept the two AI separate from the start are questions we can only speculate at since she takes the answers with her to the grave. But hey, without her, we wouldn't have this novel in the first place, so we can't complain too much.