I only have one younger brother and no other siblings, so I'm familiar with a certain kind of brotherly dynamic. The tsuma only has one older sister and no other siblings, so I'm pretty dependent on her experience to figure out what to expect from onechan and imoto as they grow up. What I'm looking for from Blogoramaville are a broader set of perspectives. Feel free to respond any time.
Imoto is almost a year and a half and onechan will be four at the end of the year, so we've already been living in interesting times, so to speak. Not so long ago, Imoto got jealous of our watching a home video from the first month of onechan's life for the first time since she was born. At times, it seems as if onechan is the "m" and imoto the "s" in a sadomasochistic relationship. We've drilled "don't hurt the baby!" so successfully into onechan's head that lately I've been sounding like a self-defense instructor: "Don't just lie there crying! She'll only keep pulling your hair!" Overall, of course, they love each other to death, and there's nothing cuter than listening to onechan chatter away in cutesy Japanese when she's trying to teach imoto something or convince her to do something. We're even beginning to feel comfortable letting them play alone together in another room for a half an hour at a time (or until the screaming reaches a certain pitch, whichever comes first), relatively confident that the metaphor in the previous sentence will remain merely metaphorical.
It's just that as an imoto herself, the tsuma tends to see things from imoto's perspective more easily than from onechan's. As an onichan, I suppose I do the opposite, although of course it's easier to see when someone else is doing it. So if we can just get enough descriptions of sister acts from the netizens of Blogoramaville, we might be able to temper our natural sibling biases enough to...I don't know, be better parents? That seems a little ambitious, doesn't it? Just give us some good stories and we'll be satisfied.