“Hey, bro,” Maia says. She bumps knuckles with him, then grins. “You came back! And Ayers tells me you’re going to work on Treasure Island.”

“That’s the plan,” he says. He glances quickly at Ayers in her white tank and light blue Lululemon running shorts; he can see the outline of a bikini underneath.

“Ayers’s boyfriend, Mick, is really jealous,” Maia says.

“Maia!” Ayers says. “Hush!”

“What?” Maia says. “He is. He’s even jealous we’re taking this hike.”

“Well, he doesn’t need to be jealous,” Cash says. “Ayers and I are just friends.”

“That’s what I told him,” Ayers says. She drops her blue aviators down over her eyes. “Are you sure you don’t mind carrying the pack? It’s got to be heavy.”

“Please,” Cash says. “I hike at eight, nine thousand feet with a pack that’s three times this weight.”

“Ayers doesn’t like hiking,” Maia says. “But she’s my parent now, so she has to do enriching things with me.”

“Mangrove snorkeling is enriching,” Ayers says. She looks up at the brilliant blue sky. “And a far more appropriate activity than hiking on an eighty-degree day.”

“Next week,” Maia says. She strides toward the trailhead. “Come on, Winnie, let’s go.”

The Johnny Horn Trail has five spurs, Maia explains. The first spur, a flat, sandy walking path, leads to a narrow beach hugging a bay that has a rugged island a hundred yards offshore.

“Waterlemon Cay,” Ayers says. “Best snorkeling on St. John. How about I stay here and you guys keep going?”

“We’ve only been hiking thirty seconds,” Maia says. She turns to Cash. “See what I have to deal with?”

The second spur takes them up a steep, rocky incline that requires a fair amount of scrambling and careful foot placement before it levels out, when they reach stone ruins. This is the guardhouse, Maia tells them, built in the 1840s, back when slavery had been abolished in the British Virgin Islands across the Sir Francis Drake Channel but was still legal on St. John.

“There were sixteen soldiers stationed here,” Maia says. “And their job was to keep watch for runaway slaves.”

Cash is impressed. “You have quite the body of knowledge,” he says. “How did you learn all this?”

“My mom,” Maia says. “She knew everything about the Virgin Islands.”

Cash nods as the peculiarity of what he’s doing hits him. He’s hiking with a half sister he never knew he had. Maia bows her head and is quiet and Ayers places a hand on the back of her neck and draws her in. They’re thinking about Rosie; Cash can feel how much they miss her. A twelve-year-old girl lost her mother, lost both of her parents, and yet here she is, bravely soldiering on with her mother’s best friend and a strange man she has gamely decided to accept as “bro.”

“Did your mom like to hike?” Cash asks.