So, I know that in the “Lovely Princess” novel that Athy read in her past life, Princess Athanasia was the elder sister (actually cousin) of Jannette, but the timeline for the current story doesn’t seem to match.
Going by how the manhwa has framed the two princesses’ origins, Penelope left the mansion pregnant before Claude met/started-a-relationship with Diana, right? And based on how close the debutante ball is to Athy’s birthday, wouldn’t it make sense for Athy to be the younger of the two? If not the younger, perhaps she was born prematurely, which might be why there is that scene between Claude and Diana in the dream/memory of him asking her to give up the baby (perhaps there were complications early on that we don’t know about yet).
I am struggling to see Jannette as the younger sister despite the multiple claims found in the text and wonder if this might be an upcoming plot element that the author is hinting toward.
I’d loved to hear others’ thoughts on this theory 😀