I just found out that my husband may have fathered a son 23 years ago before we were married 2 years later. An old girlfriend, who was currently living in Japan, showed up on his doorstep here in Los Angeles with a little boy- obviously 1/2 Asian and 1/2 Caucasian ( blond hair like my husband's). I happened to be there, and witnessed the devastation on her face. A brief uncomfortable introduction followed. This woman left. My husband denied he ever had sex with her. Until 3 weeks later when I asked him if he thought that could have been his son. He admitted to being with this woman several times, but was sure the chid was not his.
Fast forward to last night- I questioned a large sum of money that he transferred into an account I do not have access to, and the trust issues arose and the possibility of him having an illegitimate child. I asked how did she find him after 3 years, and he said she hired a private detective. He had never told me that before, insists he had.
He screwed up. How do I find out if this is his son? We will be ending this marriage and I need to know if he has any heirs besides the son I had with him.
The people search sites have not been able to give me any information I don't already have.

You make this a part of the divorce that he reveal any other children he has fathered.

And why is heirs an issue, is he expected to die soon, he may of course remarry and have a new wife as a heir, he may have several more kids in following years ?

And "trust" he had the child before you were together?? That is not trust, that is merely before.