Belén Rueda left the series in season 6 in order to focus on her film career. She later returned for the series finale.
Several actors from Los Serrano have worked before in another series, "Al salir de clase" (1996): Fran Perea (Marcos), Alejo Sauras (Raúl), Elsa Pataky (Raquel) and Leticia Dolera (Ruth).
After Guille and Teté have a relationship in Los Serrano they had one "in real live" for 5 years.
Antonio Molero is only 11 years older than his son in the fiction, Alejo Sauras, and Belén Rueda is only 12 years older than her daughter in the fiction, Verónica Sánchez.