How do I find a child of a soldier who served there in 1969?

I was married to a man who fathered a child there in 1968 or 1969. I didn't find out about the child until he died here in 1988 of a surgery complication. His friend told me of the child as we stood at the funeral service.

He married a woman there and they had a little girl. What a wonderful thing it would be to find her now.

My address is redone@infi.net

thank you.