Ernesto Lopez is an unseen character in The Ballad of Gay Tony.
He was abandoned by his father, along with his mother, brother and sister. Ernesto dislikes Luis, believing that he is "drug dealing trash". This can be seen at one point when Ernesto sends Luis an email insulting him and saying that he should come back to Liberty City to deal with him. If Luis replies negatively to the email, he will respond saying that he'd love for Ernesto to come back and deal with him, and then asks why he doesn't try to send money to their mother.
Ernesto moved out of the city and started a family, and a job as an accountant. His siblings dislike him, believing he is a "prick" and an "asshole", as he apparently never sends money to his mother and only calls her twice a year. Luis makes fun of his wife as well. During Drug Wars, Henrique Bardas will sometimes question Luis on Ernesto's whereabouts, to which Luis answers that he doesn't know where Ernesto is and "doesn't give a fuck".
There are numerous pictures of Ernesto in his mother's house that are rather hard to view as they are only featured in cutscenes. If the player should look at this pictures in his mother's house, it can be seen that they feature different characters. One wears a beige suit, a fedora, and has extremely dark skin, implying he is African-American, which is obviously untrue. Another picture shows another version of Ernesto wearing a blue jacket, sporting corn rows, and having rather light, tanned skin. The same goes for his sister, Leta.