Four Square. Yellowstone Investigations, #4

This fourth book in the series, with over 79, 000 words of romantic suspense, tells the story of Ariana and Paco.  Ariana: Father and son outings are one thing. I'm pretty sure my brother brought my father to Yellowstone National Park so he can commit murder. Too bad nobody believes me. Not even the helicopter pilot I hired truly thinks I know what I'm talking about. At least he's nice enough to listen, even when we get to my brother's campsite and find both Adam and my father are just fine.
There's a game here. I know it. But I don't know what it is. Paco: I can't put my finger on exactly what's going on with this family. They're rich, and maybe that's why they're so weird. But there's something happening here, and Ariana is convinced that her brother is about to commit murder. Maybe my job is to make sure she doesn't get herself killed trying to do what's right.