My wife is an engineer and I trained as a cognitive scientist. When my daughter was born we both fully expected her to have no interest in 'girly' things, especially as the house was already full of interesting 'boy' stuff from her brother. My wife has no make-up, a couple of dresses for formal occasions, no shoes with heels... hopefully you get the picture.
At every step she has chosen the stereotypical girl toys, the colours pink and purple, fairy stuff, pretty dresses and so on. She nagged us for make-up for dressing up, and when we said no she improvised with felt-tip pens. She dresses her dolls and puts them to bed each night, reads to her cuddly toys and hangs up her dancing dresses in order of size, colour or favoritesest.
I'm rather glad it turned out that way because she is popular at school and I know she won't suffer some of the cruelty my wife did as a child growing up slightly different to the other girls in her class.
But nevertheless it continues to amaze me that she fits with her peer group for toys, interests and preferences and it seems to have made no difference whatsoever that she is surrounded by science and 'boy stuff' at home.
And she did not play with lego at all, despite having access to large amounts of duplo, technical lego and a range of figures until I bought her the pink fairy castle set.
It bothers me too about branding things gender specific and all the pink and purple and stars and rainbows. It's a self-serving cycle and I don't see a way out short of legislation. It's harmless enough to begin with, but the danger is that no boy would be seen with a 'girls toy' or 'girls book' and that a lot of girls think 'boys stuff' is boring, or worse convince themselves they don't like it just because they think it's not for them...