My founder is frozen on day 1 of YA. It's a bit weird when everyone gets older around him. During the time when the first batch of children went to university, he had the sixth place on the portrait panel, after the wife and four of the children, which led to much confusion at first :smiley: . Of course, if you use ambrosia, a "young again potion" or a "fountain of youth elixir", you can switch those places around at will, although it's hard to beat someone at day 1 of YA.
Of course, if I play a different town within this savegame (via mods), he still ages during that time, so there's some flexibility even without just using MC within the age span.