Why do most babies have blue eyes when they are born but then, when they grow up, they sometimes turn brown?

Question: Why do most babies have blue eyes when they are born but then, when they grow up, they sometimes turn brown?
- Keywords:
  baby,
  change,
  eye colour
Asked by Aimee to Carolyn, Peter, Richard, Sara, Siana on 12 Nov 2015. This question was also asked by Daisie21, Afaf, *zoemma*, lou_lou_67.
- Sara Falcone answered on 12 Nov 2015:
  
  Melanin (the protein that gives color to your eyes, but also hair and skin) takes a little bit to be defined and accumulated. This is why a lot of babies have lighter hair color as well… I was blonde/gingerish when I was little!
- Richard Unwin answered on 12 Nov 2015:
  
  Good answer – it’s the same reason why babies are generally born without freckles or moles, but these can develop as they get older – your production of melanin (which is also the pigment that makes you go brown when you sunbathe) doesn’t kick in until a few months after you are born.

Question: Why do most babies have blue eyes when they are born but then, when they grow up, they sometimes turn brown?