The history of baby colors

From Smithsonian: "Pink and blue arrived, along with other pastels, as colors for babies in the mid-19th century, yet the two colors were not promoted as gender signifiers until just before World War I — and even then, it took time for popular culture to sort things out. For example, a June 1918 article from the trade publication Earnshaw's Infants' Department said, 'The generally accepted rule is pink for the boys, and blue for the girls. The reason is that pink, being a more decided and stronger color, is more suitable for the boy, while blue, which is more delicate and dainty, is prettier for the girl.'"