Ramon is a history buff, a member of the Philippine History Group of
Los Angeles, California, and has authored and painted all illustrations
of a book about his birthplace, "Cabugao", dating back to pre-Spanish
colonial times. He comes from a family prominent in Philippine politics
since the late 19th century. His younger brother, Jose Maria "Joma" C.
Sison, is an internationally known poet and the founding chairman of
the Communist Party of the Philippines (CPP) and the New People's
Army(NPA).