Irish Mary O'Rourke (Mary Miles Minter) comes to America to visit her sister Norah (Myrtle Reeves, who quit acting and became Mrs. Oliver Hardy in 1921). She finds that Norah married a man named John Stuyvesant and has a baby, but her husband has deserted her. Mary is outraged by this, so she snatches up the baby and takes it to the Stuyvesant home. She waves it in front of the lady of the house (Lydie Knott), insisting, "This is your son's baby." Mrs. Stuyvesant is very pleased with the baby, and with Mary, who she assumes to be the mother, and welcomes them into her home. Mary wants to set things straight, but she has been told that Mrs. Stuyvesant is an invalid and may not be able to stand the additional shock this disclosure would cause. So she stays and eventually John Stuyvesant (Alan Forrest) and his cousin, J. Frederick Stuyvesant (Charles Spere) return from Arizona. John is surprised to find he has a wife and child since he had promised to marry Genevieve Harbison (Margaret Shelby, the real-life sister of Minter). But he can't say anything, either, for fear of shocking his mother to death. Genevieve is not so patient, however -- she insists that John marry her, now. He sets it up, but Mary and J. Frederick find out about it, and they go to stop it. But when Mary pulls out the marriage license, the name listed is John Frederick -- John's cousin. J. Frederick admits to his marriage to Norah, but explains that he has been trying keep quiet about it while waiting for an inheritance to come through. Meanwhile, John realizes he's not so thrilled with Genevieve and marries Mary instead.