|Hold it right there, outlaw!|
This article is littered with spoilers, so I reckon you might ought'a mosey on down the road if you don't want to read any plot details.
During the mission "Landon Ricketts Rides Again", Marston meets Emilio while he's having a conversation with Landon Ricketts in Chuparosa about the whereabouts of Javier Escuella. He knew of an Escuella, but he did not know if his first name was Javier or not. Landon tells John that Emilio's sister, Luisa, is being held in a government jail. Ricketts and Marston then rescue Luisa from the prison. He is not seen again, although when John Marston takes Miranda Fortuna to the docks, they take his stagecoach for transport.
- Unlike his father and two sisters, Emilio cannot speak fluent English.