Ernest Hemingway Vega is the son of Hugo. He's a snappy, moody teenager who harbors a severe hatred towards authoritative figures (which has caused a rift between him and his father). However, he also has a softer side to him. He is in eighth grade.
During Damien's first date, it is revealed that he stood still for 20 minutes while Lucien built a small brick wall around him in the school basement following the promise of wine.
His rapper name (which he spray-painted onto the church pews) is Yung Steinbeck.
He is fond of pizza rolls.
In Damien's last date Hugo and Ernest will adopt Duchess Cordelia. In the epilogue, it is shown that having a dog helps significantly with his behavioral problems.
Nothing is said about Ernest's mother.
Hugo has an ex-husband whom Ernest spends weekends with and is referred to by Hugo as "the cool weekend dad".