Attached are three copies (afterward scanned) of the U.S. Federal census in Washington State (1920, 1910, and 1900) showing the family of Richard Jacob McDonald, to whom was born Louisa [Cecelia] McDonald, shown as the fourth child, 15 years old (as of 1 January 1920, when the 1920 census was begun). This Louisa Cecelia McDonald is my great-grandmother.
The marriage certificate (included) verifies that the wedding of Richard and his wife (also Louisa) took place in Wadena County, Minnesota, performed on 29 November 1899. (The copy turned out of poorer quality that the original document, although with Fold3's viewer adjustment tool, you can change contrast / brightness or invert the image for a better view.)
The census was taken in Monroe, Snohomish County, Washington state. On the census, the first location given is the place the individual was born; the second is where the father was born; and the third is where the mother was born. This, then, indicates that she was born in Washington state, while her dad was born in Minnesota, her mom in Wisconsin. Age, known information about the states where parents were born, etc., verifies that this should be the right family. With her parents thus established as Richard Jacob McDonald and Louisa McDonald, I am ready to follow the line further back.