Margret MacBride loves her children more than life itself, but as a young widow she can't support her and her children on a maid's salary. After losing their home they struggle for years to survive living on the streets of New York City. Distraught, Margret turns to the church for guidance. Sister Mary Agnus convinces Margret her children will be better off if she turns them over to the Catholic Foundling Aid Society under the care of their aid worker, Mrs. Kelly, for placement in a new home. Taken from the only home they have ever known, Elizabeth and Conner MacBride are frightened and homesick. When Elizabeth finds herself in trouble after a run-in with the foundlings home's director, Sister Mary Clare, and bullied by one of the other children, Mrs. Kelly has to put her job on the line to get Elizabeth and her brother on the Orphan Train and find them a new home in the wild western territories.