She creeps over almost shyly, with none of yesterday’s teenaged bluster. Maybe she’s feeling contrite about her blow-up, or maybe, in that foggy swirl of wildly fluctuating serotonin and dopamine levels that is the brain of a teenaged girl, she has just completely forgotten about it. But no matter how bratty London gets, Finn can never really be angry at her, given what she knows about her life: mainly, that her parents are crazy, and that she can’t even rely on her siblings to be on her team. Finn has been there.

London sits down on the dock and Finn is surprised to see that her feet are completely submerged in the river, her legs at least three inches longer than Finn’s.

“What happened to your face?” London asks, peering intently at Finn’s nose.

“Oh,” Finn says, touching her bruise. She decides there’s no point in lying about it. “Someone punched me last night at Barkley’s. A girl. Who I don’t even know. She just punched me.”

“Oh, cool,” says London.

It’s pretty apparent that she isn’t listening, or just doesn’t care. Finn tries to remember what it was like to be a teenager, to be that self-absorbed.

“Um, Aunt F?” she says again, pushing her glasses up on her nose with her finger. “Can I show you something?”

She flips open her laptop. Finn assumes she’s just going to show her some funny pictures of her friends on Facebook, or maybe an email she got from a boy that she’s unable to decipher. Something aunt-appropriate and easy for Finn to deal with at ten o’clock on a Sunday morning. But instead, she opens up a link to a news site from Minnesota and plays a video. A pretty young reporter comes on the screen.

“Most people think that, living on a lake, they don’t have to worry about sharks,” the reporter says, her face sombre. “But for one North Shore family, their worst nightmare came true.”

The camera jumps to an obese woman with dyed red hair, standing in front of a rocky shoreline. “My son and I were fishing in my boat when all of a sudden I looked out across the water and saw a shark fin sticking up in the waves,” she says. “At first I thought it must be some kid with one of those novelty fins attached to his head, but then it got closer and I could see that it was a real shark.”