I always check for a wife's estate, but rarely expect one if she dies first. I always double check for one if the wife dies last. Genealogically speaking, it is usually best that way. The estate of Charlotte Lake from Chariton County, Missouri, is a prime example of this situation. Charlotte survived her husband by forty years.
Some documents make the relationships of the heirs more clear than others.
When originally researching the estate records for Charlotte, time did not allow for a leisurely perusal of the information. Everyone was tired and cranky. I decided not to figure out all the relationships and analyze everything completely on the spot. Instead, I would copy as many pages from the estate records as I could and analyze them at home when I was rested and better able to concentrate. As she survived her husband by many years and since some children died with children of their own, Charlotte's estate provided the most genealogical information.