My baby daughter got her adorable puffin-print dress absolutely CAKED in mud crawling around the yard and my first thought was "oh no her beautiful dress"
And my second thought was "oh huh it really WOULD be easy to unconsciously steer her away from playing in the dirt. Unlike my son, whose outfits are usually some kind of solid dark easily washed pants plus a shirt that doesn't trail in the dirt like a dress does."
Anyway something something gender roles start getting shoved on kids from literal birth, but with a little time to think about things, YOU TOO can let your children of any gender absolutely destroy their clothes in the dirt pit they're digging in your garden
Years ago now, when my son was three or so, we were on a bus together, and there was a woman sitting near us with two kids around his age, a boy and a girl. We were in the front of the bus - the bit where some seats face the aisle instead of forwards - and as there weren't many passengers, both her kids were playing around on the seats; not disruptively so, but just in the way of wiggly kids trying to entertain themselves. The mother didn't say much to her son, but was constantly trying to get the daughter to settle - not because she was doing anything different to her brother, but because her dress kept riding up and flashing her underpants, which was a problem her pants-wearing brother didn't have.
And even though I'd already known about the ways in which girls are socialised differently to boys, seeing that scene play out really brought home to me how invisible a lot of those gendered lessons are. Because the mother wasn't trying to enforce a behavioural double standard, or expressing archaic views on ladylike behaviour, or anything like that: she was just teaching her child not to show her underpants in public, which is a necessary thing for kids to learn! But because she hadn't put her son in clothing where active play could lead to accidentally flashing, only her daughter was being coached to be conscious of how she played, how she moved, the relationship between her clothes and the gazes of the people around her, why it was important to sit still. And meanwhile her brother was carrying on uinterrupted, completely unaware of the lesson his sister was getting.
And the thing is, the problem is hardly inevitable. When I've told this story before, I've gotten responses from parents saying, "Oh, that's why we always gave our daughter bike shorts to wear under her skirts!" - and that might seem obvious, but that won't occur to everyone, especially if the option was never available in their own childhood. And so something as simple as a choice of child's clothing and historical ideas about Who Those Clothes Are For ends up dictating socialization in ways we might not consciously intend - and yet the consequences of it remain very, very real.