P. G. N Unnithan hailed from the Edassery Pattaveettil family of
Mavelikkara which had a history of high military service to the
Travancore royal family. His father, Ittamar Koil Thampuran, was from the
Haripad Palace and nephew of
Kerala Varma Valiya Koil Thampuran. He married Bhargavi Amma, the daughter of P. G. Govinda Pillai (government advocate at
Alappuzha) of the Pullampilla Pichanattu (Viruthiyathu) family of Chengannur, who was among the earliest women of the region to support the national movement starting with the boycott of foreign clothes at Alleppey organised and led by the veteran freedom fighter and P. G. N. Unnithan's classmate
K. Kumar of Travancore. His sister was married to the son of famed artist
Raja Ravi Varma of the royal family of
Mavelikkara. He had four children. He died on 5 April 1965. ==Legacy==