Ricardo's son traveling to camp, central to the family dynamic.
Ricardo is the responsible parent guiding Unai during the camp journey.
The character profile identifies Ricardo as Unai's father, and both travel toward the summer camp.
Marcos belongs to the adult group responsible for the children during the journey.
Marcos is described as a parent traveling with the children, and Unai is identified as a child traveling to camp.
They cooperate during the improvised plan on the train.
Nacho and Unai are explicitly listed together among the children attempting to outwit the ticket inspector.
They cooperate with the other children during the train crisis.
Unai and Fernandito are explicitly included in the children's collective attempt to deceive the ticket inspector.
They share the children's risky escape effort.
Unai and Lucas are named among the children improvising a plan against the ticket inspector.