Take a story's temperature by studying its tone. Is it hopeful? Cynical? Snarky? Playful?
Casual, Intimate
Helena is a talker—she can chat it up with the best of them. As she tells her tale, Helena keeps her tone casual and personal. Just hand that girl a hunk of cheese and a thimble of coffee, and she'll gab with you like you're old chums.
Even when Helena is being super deep and thoughtful, she still writes like she's talking to a good pal. So when she's feeling left out around her siblings, she tells us just how she feels:
I had led us away from all we knew in order to keep us together, to be family. Now look at us.
Louise (Mousie!) and Camilla as if I didn't exist. And Beatrice, who was either terrified, lovesick, or sound asleep. And Lamont gone gladly off into the unknowable world of boys. Mouse Scouts indeed. (7.78-79)
Helena's not trying to be super formal in the way she talks to us—she doesn't even worry about using full sentences. She's keeping her tone informal and intimate, almost as if she's writing in a diary or talking to her BFF, which means that when Helena tells us her feelings, it's hard not to care.