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This has been puzzling me for some time. I look at my baby photos. Up till about 3 years old I was blond haired and blue eyed. But, pictures from when I'm four my hair turned a dark brown and my eyes went hazel.

I'm not the only one I've seen this happen to. Friends had their childhood pictures where their children looked like they were directly out of the children of the corn.

Everywhere I look for any research on this just brushes this off as an increase of melanin. But, nowhere that I've seen looks into why it happens in a prepubescent stage. No research into if this is environmental, or purely genetic. In general, because it's deemed as harmless nobody has done any research beyond "your kid has more melanin then your other kid." Just wondering if anybody has seen any research come out about this that dives deeper.