Dinky (1935)

Mrs. Daniels has been framed on a fraud charge and sent to prison. By bundling her son Dinky off to military school, she is able to keep her shame a secret from him. Upon learning the truth, our young hero voluntarily pulls out of the school and takes up residence in an orphanage. But now it's his turn to hide the truth from his mother, by pretending via correspondence that he's still a cadet in good standing.