User blog comment:Doctor Ibrahim/Ferra full sketch/@comment-27550231-20160627055318/@comment-28358106-20160627061109

It's odd you ask. Actually, they do grow, but at different rates for different reasons. Aurum is our oldest at ten physical years, but she has the body of an 18-19 year old. She actually physically grew as she developed, starting at a physical age of around 9-10. Lucida is second oldest at 8 physical years, but she hasn't changed as much, starting at 14 apparent years and now appearing 16. Aegis, who is 6, is next, having started at 15 physical years and is now at around 16, though it's hard to tell. Ferra is only 3, but she started physically around 25 and hasn't changed at all.

Because they are amplified embodiments of Regina's personality, they grow over time according to their stature within the psyche. Different aspects develop at different rates, and Regina herself has come a long way since being freed, so I expect they will continue. How much, I don't know.

As much as they have developed, they are all essentially innocent souls with childish tendencies, except for Aurum, who is simply chaste and a bit idealistic. Ferra is easily the most innocent, but she has picked up some rather impish humor (and sign language swear words.)