Beside her, Mabena chuckled and placed a restraining hand upon her arm. “Easy now, Lady Elizabeth. We don’t need you falling in to get a closer look.”

Libby shot her friend a smile. “No more of that—not this summer. It’ll just be us, Mabena. No one even needs to know that I’m Bram’s sister. I think . . . I think I’ll just be Libby until we go home again. Libby Sinclair. No ‘my lady’ nonsense.”

She expected a smile of pleasure. A nod. Quick agreement. Instead, thunder flashed through Mabena’s deep brown eyes. “That will never do, my lady. You are His Lordship’s sister. You can’t just pretend otherwise. And I had better not either, lest I forget myself when we go back to Somerset.”

For a long moment, Libby just listened to the splash of water as the boat sliced through it, wishing one of her magnifying glasses could help her see what this heavy thing was inside her chest. Wishing there were a Latin name for the feeling of disappointment—no, discomfort. No . . . she didn’t know the word for this feeling that always seized her when someone disapproved of her.

Which was all the time, lately. She could all but see her sister’s perfect face looking at her in utter dismay, hear her voice saying, “For heaven’s sake, Elizabeth, can’t you just be a proper young lady for a day in your life?”

Mabena’s sigh joined the wind jostling them for elbow space at the rail, and she leaned closer until their shoulders just brushed. “You know it isn’t that I don’t want to be so informal, my lady. It’s just that it would be so easy to do that I honestly do fear I’d forget myself when we go back again. And I don’t relish losing this position when your mum or brother realize we’re friends. We walk a fine enough line as it is.”

She knew that. She did. As indulgent as Mama was about the microscope and slides and endless supply of sketchbooks, she wouldn’t budge on some things—the lines between the classes high on the list. Loyalty and some affection between a lady’s maid and a lady was acceptable. Friendship was something else. Friendship required equality, and that she’d never grant.

Were she a braver girl, Libby would defy that unspoken dictate and argue the point. She’d declare that she didn’t care who Mabena’s parents were or where she was from, they were friends and that was that. They understood each other. Shared a fascination with the natural world—something Libby couldn’t claim about any of the gentlemen’s daughters she knew. While they recoiled in horror at a worm or an insect, she leaned in for a closer look. They were too different.