This cabinet card portrait features what I imagine are four siblings. Although they look quite depressed, I believe their flat affect is more of a function of following the photographers instructions rather than the result of major trauma. The young man and three young women compose an attractive and well dressed family. The photographer, O. E. Flaten has a number of photographs in the Cabinet Card Gallery, although this particular image is the first from his Moorhead, Minnesota studio. To learn more about Mr. Flaten and to view more of his images, click on the category “Photographer: Flaten”.
THE CABINET CARD GALLERY 
Perhaps these are the grown up versions of the four children in “Plaids, Ruffles, and Bows”? Both are in Moorehead, MN, and the girls, especially the one on the upper left of this picture (and on the left of the other picture), look incredibly similar.