Stay with River

Before Simon can give an answer, you give him a nod. "I'll watch your sister if you want."
He looks surprised. "You don't have to-"
You wave aside. "Don't worry. Never like fairs anyway."
He looks at you for another second, then smiles. "Thank you."
He joins Kaylee, Jayne and Shepard Book and they leave, Mal and Inara right behind them. You watch them go, then go back inside the ship and seek out River's room. She's not there, so you walk around the ship, calling out, finally finding her looking out of the window with a wistful expression. She turns around as you approach her. "You're not going?"
"No", you say as you put a hand on her head and give her a gentle rub. "I thought I'd keep you a little company."
She smiles with an expression somewhere between gratitude and pain. "You don't have to."
"I don't mind, River."
She gives you an intrigued look, then looks out again. You still find it hard to properly communicate with her - sometimes she seems so innocent and child-like that you instinctively want to pick her up and carry her to her room to read her a story, other times she lets all that intelligence and understanding shimmer through that reminds you that she's an adult - not to mention the fact that she's a little hottie.
"You know, fairs really aren't that great", you try, only earning a pitiful look. Yeah, she's too smart for that.
Still, you don't give up. "We can have lots of fun on our own. Come on, I'll tell you funny stories."

Surprisingly, you manage to entertain the girl enough so she actually forgets about the fair. After half an hour, you sit on her bed, laughing about silly anecdotes. She's entrancing when she laughs so untroubledly. You catch yourself just gazing at her pretty face as a soft boom shakes the ship. You both stop and look at each other. "I'll better have a look", you say and get up.

The cause of the tremor quickly becomes apparent. Looking out of the window, you see the fair in complete disarray. A circle of destruction and dead or injured bodies everywhere indicate there has been an explosion. Before you can prevent it, River comes up behind you and looks outside. "I'm going to the fair", she says.
"What?", you ask as you turn your head. "River, we'll stay here, I'm sure the others will come."
You're not sure if this is the right choice, whether you should look for them, but you can't leave River alone here. So you pick her up again and go back to her room, and then you both wait, anxious and unable to talk as relaxed as before.

But indeed, a few minutes later, Mal and Inara return to the ship, looking quite shaken. As you open the cargo bay gate, the captain walks up to you. "John, I need you and Inara to watch River for a while. Alliance needs our ship."
"Alliance?", you ask curiously, but noticing the look on the captain's face, immediately add "Sure."
River gives an odd smile and says "Purple elephants are flying", earning confused looks from everyone.

Now you notice more people approaching. A tough looking soldier woman in her 40s and two skeevy looking bounty hunters. The soldier stops and looks at you, then says "My apologies for the inconvenience."
Inara nods. "It's no problem. I hope you catch the monster responsible."
"We will", the woman says and gives River a curious look, but is then distracted by Mal.
"If you’ll stop bothering my paying customers, we can be off."
"There’ll be three others joining us", the soldier says as another man, looking like a farmer, in his 50s comes into view. He doesn't stop and just walks straight into Serenity as the others follow.

"Come on", you say and take River's hand.
"Simon's in a tent over there, treating the injured", Inara tells you. You nod and follow her lead. All around there is a flurry of people not really knowing what they're doing. As you enter the white triage tent, you spot Simon bandaging a drooping man around his ribs.
"Simon", River calls. "Simon. The fair."
She runs over and hugs him. "Cotton candy. Play. Play!"

Simon gives a pained look. "I need some help here. And can one of you watch River?"