Hilda, otherwise known as La Gorda (The Fat One) behind her back, is a girl from Marina's orphanage in Santa Teresa.
During a visit to a nearby mountain camp during one summer, Marina plays Queen of the Dock with the other girls. She doesn't hear Hilda approach before she is shoved off the dock and knocked unconscious by hitting her head on the way down. Marina gets trapped under the dock and almost died until she discovers that she can breathe underwater.
Hilda is inseparable with her friend Gabby and assists in making Marina's life difficult. She is scared by the rocking chair caused by Marina when she won't allow Marina on the computer, along with Gabby and later accompanies Gabby, Delfina and Bonita to the nave at night where they confront Marina about her behaviour. She is thrusted backwards by Marina's telekinesis and gets up, prepared to charge like an angry bull. She is knocked out by a strong punch to her chin by Marina.
The next morning all four girls were found by Sister Lucia in the nave, they were assumed to have been up to no good and were taken back to their bedroom, dazed and bruised. Later as Hilda examines her bruises from the fight, Marina walks in and in fear she tries to focus on washing her hands.
La Gorda is present during the Mogadorian attack on Santa Teresa and it unknown what happens to her during the battle.