If Alfi ever visits the Imperial Palace at Berlin before he's 14, perhaps with his family as formal guests? Then I can see him and Millie being acquaintances, fellow peers of high society or something like that, haha. Whaddya think?
I kind of have a background thought for him and I definitely could see his parents/family visiting other families. I think, I am going to have Alpheus's and his siblings kind of be that noble family that has kids to arrange to other nobles/royal families to help keep the genetic pool broadened except Alpheus's diagnosis would have booted him out quickly from that so he just kinda did a bunch of visits to learn about different families.
I could see him being at the royal empire just because his parents dragged him along and him getting in trouble with the cooks and bakers because he steals a pastry or a roll or two.