Colours used for children's clothing have gender symbolism - this is most universally represented by blue for infant boys and pink for girls. Yet it took many years for this colour code to be come standardised. Pink and blue were associated with gender by the 1910s and there were early efforts to code the colours for one sex or the other.
As late as 1939 a Parents Magazine article rationalised that because pink was a pale shade of red, the colour of the war God Mars, it was appropriate for boys. On the other hand, blue's association with Venus and the Madonna made blue the colour for girls.
Confusing isn't it?
In practice, the colours were used interchangeably for both young boys' and girls' clothing until after World War II, when a combination of public opinion and manufacturer's clout pressured pink for girls and blue for boys - which still holds true today - partly as it easier for people to recognise whether a baby is male or female.
But once they are out of their nappies and have a point of view they will want to look "cool". Fashion and peer pressure take over.
Kid's clothes are not cheap - so why not try an online colour analysis with your little ones and bring out their true colours.
It will be fun :)
PS - I have teamed up with a leading children's clothing retailer - https://www.gbcrew.com/ they stock the latest top children's designer brands - drop me a line and I'll send you the 10% discount code that cam be used on all non sale items. :)