Wow, that is a fascinating thread and you are on a fascinating journey! Thank you for sharing that with me! (Incidentally, I have had some experiences with my flock which support some of your theories, especially with chickens naturally developing clans based on their physical appearances, as well as the protective and supportive behaviour of our head rooster with his chosen hens.) In fact, the spot where Celine has been singing the egg song from (it's unmistakable to me, exactly the same as the older girls sing it) is where my head cockerel paces nervously like the expectant dad he is, while his two chosen girls lay their eggs. He hops up there after kicking all the younger pullets out of the coop when one of his ladies wants to lay, then paces while she gets comfortable (and her sister waits her turn outside the box). When the both are close to done, he runs to heard all of the flock back into the coop, and his ladies sing the egg song together. It seems as if he's proudly showing off his new baby to the whole flock and celebrating his hens' accomplishments...though that's likely me just putting those human emotions on them.
I guess my big question with my hen in question, Celine, is that she is still so young and I have never known a pullet to enter this phase of her life at such a young age, though it seems that my chicks that I have raised here have all matured faster than I had anticipated they would based on common wisdom.
The Discovery of her found blue egg really was a shock to me. I don't know at all how to interpret her stealing that egg (to be fair, I didn't see her steal it but somebody did, and she was the one being vocal about it and preparing a nest, so all signs point to her). Have you ever known a hen to steal others' eggs and try to claim them as her own??!?
I know, none of this matters in the scheme of things, and she will eventually begin to lay her eggs sooner or later, but these chickies and their behaviours are absolutely fascinating to me so I love to try to understand why they are doing what they are doing