I think that Chapter 13 "One of the Populace" is my favorite part of A Little Princess. You know that tv commercial a couple years back--I think maybe it was for an insurance company but I could be wildly wrong--showing a long chain of people doing random kindnesses for a stranger in passing, which was witnessed by a third party who was then inspired to do a random kindness for a stranger in passing, which was witnessed...and so forth? Chapter 13 it a bit of that, showing how an act of selfless charity can touch and chance the hearts of others unknown.
The chapter begins with a contemplation of the power of imagining, when Sara and Becky are commiserating after a hard day and, instead of telling stories reframing their lives as The Prisoners in the Bastille, Sara paints an idyllic story of the life the Indian Gentleman's monkey led before being captured and brought to England. When Sara asserts, "What you have to do with your mind, when your body is miserable, is to make it think of something else," Becky question whether that's really possible. In a very human moment, Sara admits, "Sometimes I can and sometimes I can't." Then she talks about the power of her princess persona. This segues into "one of the strongest tests she was ever put to" which forms the rest of the chapter.
We are shown the depths of Sara's most dreadful day, when the weather conspires against her, and Miss Minchin has refused her food as a punishment for some unstated transgression, and she's trying desperately to imagine herself into warm clothing and the most luxurious meal she can imagine: six penny-buns hot from the oven at the bake shop, which she would buy the a sixpence she imagines herself finding. And then...she finds a coin. (We learn later that she still has the sixpence that the Carmichael boy gave her for charity. But I have suggested that to actually spend it on such basic necessities would make it charity, and not the keepsake of a friend that she chooses to consider it.) The coin isn't even the meagre fortune she has imagined, but only fourpence. But there it is, right in front of a bakery, with hot buns just been put into the window display. Surely it is A Sign.
And then she sees the second Sign: a barefoot, rag-clad, freezing, starving beggar girl sitting on the steps of the bakery. Sara speaks to her and is struck to the heart at how much worse off the girl is than she herself, and her Princess Nature kicks in. If she is truly a princess, then it is her duty to give largesse to her people, even at great cost to herself. So she decides to share her small fortune with the girl.
This is the exact point at which the balance begins to assert itself. The owner of the bakery, impressed by Sara's honesty at first asking if anyone has lost the coin she found, and noting Sara's hungry look, impulsively gives her sixpence worth of buns for four. Sara, instead of splitting the six buns evenly, gives five of them to the beggar girl and keeps only one for herself. And when the bakery owner notices this--though not in time to speak to Sara again before she leaves--she is touched and a little shamed to think that a girl who was herself cold and hungry could give so much when she had barely noticed the presence of a starving child literally on her doorstep. So she invites the beggar girl inside to warm herself and tells her to come back any time she'd hungry. As we will learn much later, this is the first step toward a deeper relationship where she takes the beggar girl on as an apprentice and gives her a home. To be sure, it's only one beggar out of no doubt many on the streets. But it will turn that one person's life entirely around.
Though Sara doesn't know it yet, everything is looking up from here on. But there are diversions to endure first. Sara will undergo one more crushing disappointment before The Magic comes. And in echo of that, she passes Mr. Carmichael leaving his house on the trip to Moscow in a vain quest to locate Captain Crewe's lost daughter.