By the time thats a thing, it'll probably be a decade and a half from now since IIRC you don't activate your Sharingan for quite a while.
Also, since ninja don't really do much before the age of twelve, we can likely keep that under wraps for a while if it is the case.
As a general observation, I think its best to keep in mind that this deal is a mid to long term obligation that we wont see the true negative effects of for quite a while. In ninjadeathland, that is a truly massive amount of "If"'s to have in a deal. If your deal is reliant on a particular Chunin surviving another couple years, you are a truly desperate pile of motherfuckers, because thats extremely unlikely in universe. Given that Hazou and co manage to flip the table and subsequently slam dunk it through the floor every 9 months or so, I don't really have much faith that the deal will remain the same by the time the child thing becomes relevant.
Its far more likely that everything will be a burnt crater with everyone dead, reality itself will succumb to a hundred sealing failures, or we'll have escalated to the point where renegotiating is at least possible--if not entirely trivial.