J. Michael Straczynski, a creator whom I admire, once said, "No cute kids, no cute robots!" when referring to his most famous show, Babylon 5. Straczynski was stating that his TV show wouldn't have an annoying sidekick like Twikki from Buck Rogers or an annoying kid like Boxey from Battlestar Galactica. I realize that "annoying" is a very subjective word, but I'm pretty sure I can get a fairly high level of agreement regarding these two characters.
The robots in MoS aren't disturbingly cute - they're designed to a large degree with function in mind - but there's no way we could keep Wei from being a cute kid. However, I'm pretty sure she's not annoying - at least, not to the reader; all little brothers and sisters annoy their elder siblings.
I'd apologize for breaking Straczynski's dictum about cute kids, but I figure the odds of Mr. Straczynski reading this webcomic are about the same as my odds of winning the lottery. (The odds of me winning the lottery are approximately zero, since I don't play the lottery.)
I wonder what "fun" Benjamin was just saved from. That aside, you may if you wish take this page as evidence that, when the mood strikes me, I can in fact draw characters who are less than thirty years old.