I have two half-sisters who do not know of my existence. About seventeen years i came very close to allowing myself to be introduced to our father. which might have blown his secret (which had now become mine also). I am grateful that i have kept this secret, since its knowledge would have harmed people and not done anybody any good. Our father is dead now and he, apparently, took our secret to his grave. I shall do the same. Since my mother is also deceased, there is no one left, so far as i know, who knows the secret..