Ernesto Lopez is the oldest son of Adriana and Mr. Lopez, and the oldest brother of Luis Fernando Lopez and Leta Lopez-Wilkinson. He was abandoned by his father along with brother and sister. Ernesto dislikes Luis, believing that he is drug dealing trash. He moved out of the city and got a family, and a job as an accountant. His siblings dislike him, believing he is a prick, as he apparently never sends money to his mother. Luis makes fun of his wife too. It is revealed that Ernesto only phones their mother twice a year.
Little is known about Ernesto's personality but from Luis and Leta's conversations, and the emails he sends to Luis, he seems to be disliked by his siblings. His opinion of Luis is very low and he regards him as "drug-dealing trash". He also seems disconnected from his family as he apparently told his children that Luis was dead, and very rarely contacts them. Unlike Luis and Leta, Ernesto seems indifferent to their runaway father. He also never sends money to his mother, despite the fact that he has a stable job.
- Whenever Luis get drunk alone in either Maisonette 9 or Hercules, he will drunkenly mention that Ernesto is an asshole.
- During one of the Club Management side missions, Dessie asks Luis to go pick up the Blue Brothers and bring them back to Maisonette 9. Luis complies, but states he's only doing so because his niece is crazy about them. Considering the fact the Ernesto and Luis hardly talk, and that his kids think their uncle Luis is dead, it can be implied that it is actually Leta's children he is talking about.