Her boy (1918)

When the United States enters World War I, the widowed Helen worries that she will lose her only son David, who has just turned 21. Although David patriotically urges the employees at his factory to enlist, he reluctantly gives in to his mother's pleas to remain at home with her. When David is drafted, his panic-stricken mother alters the date on his birth certificate, although the later birth date implies that he is illegitimate. Disgusted, David enlists under an assumed name, thus shaming Helen, who confesses her dishonesty to the townspeople. Her son, now in uniform, then forgives her.