And this also explains Santiago's behavior in the flashback a bit. If he's Valeria's father, then he got her mother and Emily pregnant at about the same time. Dude was partying left and right, his parents chose Valeria's mother for him to settle down when he got her pregnant, he still planned to keep Emily as his side chick because he was young, dumb and horny.Exactly my point in thinking he is her father. You ignore your dad if he asks something like that after overhearing her arge with someone like she did with Zach, (she told him to put her down twice). Had he just been an agent scouting, she would have talked to him.
Then he learns she's pregnant, tells her he will fix everything, goes to his parents to call off the wedding, saying he prefers to be with Emily if both are pregnant, they try to pay her for an abortion, fail, she thinks Santiago asked for that, starts avoiding him, he marries Valeria's mother. It's an unhappy marriage and Santiago ultimately leaves Valeria and her mother and marries Gabriela.