First off, this is a very traditional preschool age clothing in the former Soviet Union countries, as well, as I suspect Eastern Europe, and also (historically) Germany. Not sure about the bordering countries. I linked a couple of images, and as you can see, those tights are explicitly "masculine" (as much, as it applies to cute kids clothing) and have nothing to do with cross-dressing. Or the country's folk culture, if some of you wondering.
Second, the US and perhaps UK picture footed tights as ballet attire or some "thermal" sports clothing worn under the hockey and (American) football gear, and in my own experience under one-piece leather motorcycle racing suits. The ones I'm talking about here are a much thicker "winter" kind.
Third, it is as much of a childhood symbol for me, as diapers for 99% of you here. At least when it comes to boys. Girls in tights (of all sorts) is nothing special. They wear them all their life. But boys, at least in my home country, considered tights a humiliating toddler attire once they reached the school age: seven. Though many moms still made them wear those up until probably 10. Right now those embarrassing memories of being seen in tights are rather sweet. It's changing, and the Western "adult" style clothing e.g. diaper-hiding baggy pants/jeans are very common now, but they weren't during my childhood.
And fourth, due to the design and also thicker fabric those tights are very absorbent, and can contain messes, when the kid has an accident. Of course they'd be wet, so no sitting on (expensive) furniture, but no puddles on the floor (for the most part). Very similar to training pants. And nowadays they are frequently worn over a diaper due to being so stretchable. Not hiding the diaper at all - basically the same, as being made to wear just a diaper and a t-shirt. Only one can be taken in such attire outside instead of staying at home with no pants. Imagine the humiliation potential.
There were no Western style disposable diapers in my childhood: too expensive. Probably the cloth ones (just a triangularly folded diaper cloth), which I can't remember. It's so much hassle for moms laundry-wise, everyone potty-trains their kids early aka "elimination communication" technique here, practiced for completely different (environmental) reason. Back in my childhood moms would rather deal with infrequent accidents until the age of four, than wash cloth diapers.
I don't expect to find many people here with a similar experience (maybe if I posted it in German). What do you think in general? Cute? Babyish? Would you wear them in your AB fantasies and reenactment games? NOT for cross-dressing.
Here's the AB version (wherever he found them): http://diaperandonesie.tumblr.com/post/95073746209/diaperbaggyboy-my-friend-said-that-i-should
Check him out: http://diaperandonesie.tumblr.com. Tons of AB onesies: from one-piece PJs to the classic legless ones.
And the kids ones, so you know they're not just made for ABs. 😃
http://www.pchelkindom.ru/published/publicdata/DB32681M/attachments/SC/products_pictures/IMG_2868%20copywk_enl.jpg
http://cdn4.slus.name/ad/d6/add60e9762db99febb23b693b19b9990.jpg