I remember that Derek did not want kids because he knew he'd end up with the responsibility. Fred reassured him many times over that wouldn't be the case, but the kids are what, 1.5 now? And Derek is alone with them in LA. I think Derek's probably the one who wanted to make the move though, I would guess they have several nannies as well. I would think that Fred would miss them terribly though. I can't see him living full time in LA, his business is in NYC and his heart is in Sweden.
Ryan will do anything for a deal, I would like to see him get to retire early though to spend time with his kid. It's really interesting that Emilia was so superstitious about her pregnancy that she didn't post on social media at all about it and you could tell she really didn't want to be on camera either.
As for Luis having a kid, by now the baby should've been born if he knew the gender back in the winter.