If we assume that Aglaea is the birthing mother and Cipher is the futa, and neither will go into any equivalent of menopause, and that both met lorewise around teenagehood for Cipher and early 20s for Aglaea
If we extrapolate their lifespan to the point of both of them being just over a thousand years of full on baby making, with human gestation = 9 months (0.75 years). That means the theoretical maximum births/year = 12 divied by 9 = 1.333… births per year which is around 1333 children without accounting in the humanly possible twins, triplets and quintuplets, but if we add them in with the Hellins-law style probabilities (twins = 1/89 = 0.011236, triplets = 1/7921 = 0.00012625, etc.) the expected children per pregnancy = 1 + 0.011235955 + 2x0.000126247 + … = 1.0114927, which yields = 1.0114927 x 1333.333… = 1348.66, so roughly 1349 children over 1,000 years

Thats a lot of babies