For various reasons I don’t know my full genetic background, yet I have always known my family: it’s the people who raised me. I would never consider a genetically related stranger to be family, nor would I be interested in getting to know them.
Always be your children’s true family and help them build a conception of themselves and where they come from that far transcends genetics. Their creation shows that they were truly wanted and was just the first expression you and your wife’s pure love for them