Unfortunately these days, trust is eroded with nasty divorces that come from affairs producing illegitimate kids. The other case may be for genetic diseases in the family including unknown. Chances are, he either has seen the damages biproduct of this in his own family, or likely has had it happen to him, it’s produced an innate distrust in current marriage stability as a whole, he went to this to protect himself. I wouldn’t be too upset. He didn’t accuse you of it, but i saw an uncle taken for 18 years with one legitimate kid, and 2 later that he raised from my aunt’s affair that divorced him after they became an adult and went to live with the white trash trailer park shit that created the other two. And that is the boomer gen that did that.