This film was shot during the pandemic situation (COVID). The young actor wasn't able to get physically in contact with any other actor during the shooting (due to Spanish protocols).
The kid performing the co-lead role was acting for the first time. He didn't even audition for any role before.
Ruth Gabriel won the Goya for Best New Actor in 1994 for Días Contados, directed by Imanol Uribe.
Fele Martínez won the Goya for Best New Actor in 1997 for Tesis, directed by Alejandro Amenabar.