Who was Mavshibai and what was her specific method of serving Sai Baba?

Mavshibai, whose original name was Venubai Kaujalgi, was a deeply devoted, mature-aged widow whom Sai Baba himself called "Mother" (Aai). Her service to Baba was unique and exceptionally vigorous. According to Chapter 24, while pressing Baba's stomach and side, she would become so absorbed that her breath was uncontrollable. She would twist and churn his stomach with both hands, a process compared to "grinding" or churning a pot of buttermilk. Despite this extraordinary and seemingly harsh way of pressing, which made Baba's stomach and back appear flat, Baba remained completely at ease, accepting her service as an act of pure, guileless love.