ok so imagine there's a strap-on with a reservoir where one can load a semen sample in and ejaculate it during PiV sex, potentially impregnating their partner. the semen sample need not be theirs, right, so in principle this divorces "the person who had sex with someone's mum to conceive them" and "the person who gave them half their DNA via sperm". And if you'd ask me who the biological father of the resultant child is, i'd argue it's whoever's semen was in the reservoir, not the guy who had sex*

ok, now imagine the semen sample has somehow been synthesised in a lab combining the DNA of various people rather than coming from a specific person. this complicates our inquiry into the concept of "biological fatherhood" even more, right. you could say all those people are collectively the biological father, or that going by DNA share they're more like grandparents or great-grandparents or whatever, or that really we should abandon the concept as irrelevant. But you still wouldn't call the strap-on guy the biological father (for simplicity we're stipulating he's none of the DNA sources). if he raised the kid, you might call him the father on that account, but if he didn't then he's sort of just... an enthusiastic artificial inseminator, i guess.

...

so in conclusion this is why i think it's incorrect to say Elfangor-Sirinial-Shamtul is Tobias' father in any meaningful sense


*potential complications if the sperm donor isn't a man but setting aside those for the moment