According to an article in The Smithsonian, back in the 1800's baby boys wore pink because it was considered a stronger shade and therefore more appropriate for them. The girls got blue because it was considered a more delicate, appropriate shade for them.
It seems we haven't discovered a specific reason or an event in history to justify the current tradition of blue for boys and pink for girls; but the tradition continues and no doubt the new royal baby boy will be receiving some blue garments. The Smithsonian continues to say that "Today's color dictate wasn't established until the 1940's, as a result of American's preferences as interpreted by manufacturers and retailers" (and no doubt the same happened in Britain). It could have "gone the other way", says historian Jo Paoletti, who added that "Baby boomers were raised in specific clothing. Boys dressed like their fathers, girls like their mothers".
When you meet a newborn it is difficult to know what gender they are, unless you know the parents. So, perhaps we became accustomed to using this gender-specific colour coding to avoid embarrassment of getting it wrong. Most girls go through a big pink fairy-princess phase, for which there appears to be no blindingly apparent reason, although there have been studies revealing that the majority of women's colour choices lean towards the red end of the colour spectrum.
It doesn't necessarily follow that girls adopt their mother's style either. A cousin's four year old recently wore a heavily layered fairy dress in the sweltering heat and when Mum recommended she wore something cooler, to which she responded "no, I want to look nice". Mum is, and always has been, a tomboy, so there was no adopting Mum's style here. Similiarly, a friend's daughter wanted to wear the school uniform trousers like the boys and not the uniform dress because she didn't want to look the same as all the other girls.
So, it seems that we develop our own tastes and preferences in clothes and find the colours that we like rather early on. Most young children appear to choose their clothes based on colour or pattern or a picture on their clothing. Parenting expert and author Meri Wallace says "having a favourite colour makes them unique...It's all about, I can choose."
As adults, we dont always have time to think about our favourite colours to wear or whether it really suits us and we often fall into habits such as wearing black for work "because it's easy", or pulling on leggings "because I haven't got time and nothing else fits". Having a few trusty neutral items to fall back on is fine, but if sticking to what you know means constantly choosing the same colourless pieces or ultra-casual clothes, then you are missing out on looking and feeling your best. Remember how you used to love wearing that little red dress, silver shoes and pink cardigan?...