Accio and Manrico are siblings from a working-class family in 1960s Italy: older Manrico is handsome, charismatic, and loved by all, while younger Accio is sulky, hot-headed, and treats life as a battleground — much to his parents' chagrin. After the former is drawn into left-wing politics, Accio joins the fascists out of spite, but his flimsy beliefs are put to test when he falls for Manrico's like-minded girlfriend.
Unfortunately the movie My Brother Is an Only Child is not yet available on HBO Max.
| Art | Francesco Frigeri | Production Design |
| Production | Riccardo Tozzi | Producer |
| Costume & Make-Up | Maria Rita Barbera | Costume Design |
| Production | Gina Gardini | Delegated Producer |
| Writing | Sandro Petraglia | Story |
| Sound | Bruno Pupparo | Sound |
| Production | Bruno Ridolfi | Executive Producer |
| Production | Giovanni Stabilini | Producer |
| Production | Marco Chimenz | Producer |
| Production | Matteo De Laurentiis | Executive Producer |
| Directing | Gianni Costantino | First Assistant Director |
| Production | Gianni Costantino | Casting Director |
| Writing | Daniele Luchetti | Story |
| Editing | Rosanna Palma | Assistant Editor |
| Directing | Marco Diotallevi | Assistant Director |
| Directing | Michele Corona | Assistant Director |
| Art | Roberto Benetti | Prop Designer |
| Costume & Make-Up | Gianfranco Mecacci | Makeup Department Head |
| Crew | Ernesto Busillo | Video Assist Operator |
| Sound | Marzia Cordò | Sound Editor |
| Costume & Make-Up | Francesco Pegoretti | Hair Department Head |
| Directing | Stefano Bartolomei | Assistant Director |
| Production | Carmela Compagnone | Production Accountant |
| Sound | Simone Carnesecchi | Boom Operator |
| Writing | Stefano Rulli | Story |
| Production | Marco Frugoni | Accounting Clerk Assistant |
| Camera | Ivan Casalgrandi | Camera Operator |
| Production | Raffaella Ridolfi | Unit Production Manager |
| Costume & Make-Up | Marzia Nardone | Assistant Costume Designer |
| Sound | Francesco Cucinelli | Sound Mixer |
| Sound | Sergio Basili | Foley Artist |
| Production | Christian Scacco | Production Secretary |
| Camera | Benedetta Bindi | BTS Footage |
| Production | Tea Cappiello | Production Secretary |
| Costume & Make-Up | Francesca Montiroli | Makeup Artist |
| Camera | Maurizio Zampagni | First Assistant Camera |
| Production | Paolo Venditti | Production Manager |
| Editing | Francesco Garrone | Assistant Editor |
| Production | Michele De Leo | Accountant |
| Art | Vladimiro Cecconi | Property Master |
| Production | Daniela Macrillò | Accountant |
| Camera | Philippe Antonello | Still Photographer |
| Art | Patrizia Alfonsi | Assistant Production Design |
| Costume & Make-Up | Cinzia Fabbri | Assistant Costume Designer |
| Costume & Make-Up | Sharim Sabatini | Hairstylist |
| Art | Atos Mastrogirolamo | Set Decoration |
| Lighting | Gianni Gentili | Chief Lighting Technician |
| Crew | Simona De Laurentiis | Post Production Supervisor |
| Directing | Gianluca Mizzi | Second Assistant Director |
| Costume & Make-Up | Alberta Ceccarelli | Seamstress |
| Production | Antonio Pennacchi | Research Assistant |
| Sound | Daniela Bassani | Sound Editor |
| Sound | Gianluca Basili | Foley Artist |
| Costume & Make-Up | Alessandra Stella | Assistant Costume Designer |
| Directing | Paola Bonelli | Script Supervisor |
| Production | Fabio Conversi | Co-Producer |
| Camera | Michele Paradisi | Second Assistant Camera |
| Camera | Mauro Pezzotti | Key Grip |
| Crew | Francesco Petrazzi | Stunts |
| Crew | Umberto De Luca | Stunts |
| Camera | Simone Barbona | Grip |
| Crew | Massimiliano Ubaldi | Stunts |
| Camera | Patrizio Marra | Grip |
| Production | Piero Proietti | Extras Casting Coordinator |
| Production | Anna Lollobrigida | Extras Casting Coordinator |
| Crew | Sal Borgese | Armorer |
| Camera | Massimiliano Lanciotti | Grip |
| Production | Theo Benzakein | Production Assistant |
| Crew | Alessandro Borgese | Stunts |
| Crew | Paolo Antonini | Stunts |
| Lighting | Piero Quaglietti | Gaffer |
| Lighting | Stefano D'Offizi | Gaffer |
| Production | Edoardo Peschisoldo | Production Assistant |
| Crew | Giovanni Battista Squillace | Generator Operator |
| Crew | Alessandro Novelli | Stunts |
| Production | Tonino Proietti | Extras Casting Coordinator |
| Production | Daniele Esposito | Production Assistant |
| Production | Fabrizio Fabrizi | Production Assistant |
| Lighting | Claudio Gallicchio | Gaffer |
| Production | Tommaso Vozzi | Production Assistant |
| Crew | Diego Guerra | Stunts |
| Sound | Franco Piersanti | Original Music Composer |
| Writing | Daniele Luchetti | Screenplay |
| Camera | Claudio Collepiccolo | Director of Photography |
| Editing | Mirco Garrone | Editor |
| Writing | Sandro Petraglia | Screenplay |
| Writing | Stefano Rulli | Screenplay |
| Writing | Antonio Pennacchi | Novel |
| Directing | Daniele Luchetti | Director |
