Are there time periods in your ancestor's life that are not accounted for? What was he or she doing during those periods? Where was he or she living? The first five years of my ancestor's life in the United States were a complete mystery to me. John Ufkes came to the United States in the spring of 1869, settling in Illinois. He cannot be found in the 1870 census and there is no record of him until his marriage in 1874. His life is well documented after then until his death in 1924. There are a variety of land, court, census, church and other records fairly clearly documenting his life in Adams and Hancock County, Illinois.
I realize five years is not a long time in the life of an adult, but the gap in information always bugged me. Since the time period was short and other items were more pressing, I really never worked on those five years, but they were still in the back of my mind.
A cancelled homestead claim in Franklin County, Nebraska, indicated that John spent at least one of those five years in Nebraska. That was NEWS to me and explained the "gap."