Roxy straight up says she can't actually get pregnant from sex, you need "a big boom lots of fire" to make more of her race and MC implies that it'll be something to ask Lyx for help with later on. As far as I can tell, Lil Roxy doesn't count as MC or Roxy's kid since she's literally just a younger version of Roxy, so she doesn't count against the "1 kid out of the Nexus per mother" rule.
Quarinah is busy with her mental health, but teases MC that he's never met her in the real world (only in dreams) to even get her pregnant ("no physical body, no baby"), then mentions starting a family with her isn't completely out of the question even with just the dream form(s) MC interacts with. She actually likes the idea of starting a family with MC, it's just not something she's ready to do at the moment.