Who was Saraswati Gangadhar, and what was his family's special connection to Shri Narsimha Saraswati Maharaj?

Saraswati Gangadhar is identified in Chapter 0 as the author of the 'Brihat or Thorale Guru Charitra'. His family, with the surname Sakhare, had a profound connection to the protagonist of his work, Shri Narsimha Saraswati Maharaj. An ancestor of his, Shri Sayandev, had received the grace of the Maharaj and was given a boon that 'My constant service will be performed by your descendants.' As the fifth descendant from Shri Sayandev, Saraswati Gangadhar's act of writing the detailed biography is framed as a fulfillment of this ancestral duty and divine promise.