Don't we all!?
Now, I'm thinking out the marriage rituals of the WH40K universe. That's one major thing...the fluff goes into great detail about everything EXCEPT romance, courtship, marriage, sex and procreation. The closest thing we have to references of parentage is the LACK of it, when it comes to the Schola Progenium, who takes in the orphans left behind by the endless wars fought by the Imperial Guard.
(That's a lot of orphans, so you know)
And a few references to babies being born in the mixed gender regiment as detailed in the Ciaphas Cain books, as well as one reference to a courtship between two nobles in the Enforcer series of books...
Which means, I get FREE REIGN TO LET MY IMAGINATION RUN WILD!
Bua
AHA
AHAHAHAHAHHAHAHA!