I would not read too much into this.
Basically people either have them constantly since a young age (the degree varies, though), only rarely get them after an especially rough period (respiratory illness, lack of sleep, drugs), or some people pretty much just don't get them at all.
I have seen kids who had more pronounced dark circles than Madeline at an even younger age. Having breathing-related problems in the childhood (adenoids, asthma, allergies, sinus infections) and just having a pale and thin skin seem to have notably more to do with it than sleep length, actually. Also anemia and even dehydration. More details
here.