First off, I don´t own the game, so I apologize for not being able to give you a reliable answer.
The actual marriage thing, I believe it does occur. I haven´t been able to see it in the streams (I didn´t watch any completely) but there is a magazine scan (I´m not sure if it was a famitsu scan. I´m referring to the one that confirmed marriage and children were back) in which it showed some sort of cg in which the two characters appeared to be in the wedding ceremony (In the scan it was male Kamui and Felicia).
As for the children, I don´t really know how they appear, but I can assure it is not the natural /born-time passes- child is old enough to fight with you/ thing.