It's the screaming that gets his attention. It would get anyone's attention, really, but it's not that far from him, and then it's followed by repeated words in Spanish, words that express what seems to be the opinion of just about everyone when they first arrive here.

He wouldn't bother if it weren't obviously a child doing the screaming, but a child in distress is something he can't ignore. Then as he gets closer, he notices that she's punching the rocks but sustaining no apparent injury. That's interesting.

He addresses her in Spanish, since that's the one language he knows she knows right now. "There is no getting back. At least not yet." He's not saying it in a cruel tone. Rather it comes across as a message from someone who understands completely the desire to be somewhere other than here.