Looking for neice and nephew in Okinawa

[maekay]

I am looking for Kaori Nakachi (30-39 year old, female, from Japan). I am looking for my neice and nephew. They last lived in okinawa. My brother was stationed over there in early 70's. His name is Kenneth Ellis. My parents wrote to her for several years until they passed away I tryed writing but got my letter returned saying she had moved. Please if you know of her let her know I am searching for them. Maybe someone knows what i need to do to go about searching for them. have tryed online but to kno luck