I am an analyst by training, that is what I do so when I look at a family pedigree I look for things that do not fit with known knowledge and the commonly accepted pedigree of the O'Kellys of Hy-Many is an example.  If my reader will review the data at Wordpress on the history of Life expectancy they will find that until about a hundred years ago our ancestors did not live very long.  To live to 60 years was the exception and not the rule, to live to 90 would be like living to 105 today, it happened I have no doubt but it was rare.  I suspect in most cases generations were 20 years or less between father and son, some may have been 15 years and many of the men listed below were likely born to a teenage mother and a father not much older. 

Our ancestors lived a much different life from out own, until recent times they lived and sometimes died just from during water because the knowledge of boiling water to make it safe only became know in the 20th century.  Because water carried on short journeys could become deadly quickly, to the surprise of many our ancestors dranked beer from cradle to grave.  The process of making beer required boiling and our ancestors were unknowingly purifying their drink. Our ancestors truly lived a much different life than we have been told and that is why the Pedigree of Kelly must be missing some generations, they just did not live as long as some are represented..

When I use a very conservative 25 year generation something that would be more common today we find a dozen missing ancestors in the traditional and widely accepted pedigree of the O'Kellys of Hy-Many.  Dermott #9 isn't even in many trees but there should be someone at #9 so Dermott will do since he appears in some other trees. Dermott is reported to have been King for 60 years and if that were true, he would have lived to a very unusual age of 78.  Not impossible but rare.

I am certain some are asking why this matters.  What difference does it make if some generations are missing from the pedigree?  As far as knowing the ancestors one descended it isn't important but DNA is based upon how many generations exists between you and a shared ancestor you may have with a DNA match so it is a very big deal when using DNA to attempt to discover who that shared ancestor might be.  In my case it determines if the common ancestor that I and the current descendant of Hy-Many share lived before or after Teige of Clontarf so every blank below is a missing generations and must be consider in DNA analysis.  I don't need to know their names only that they lived and produced children, sthus causing DNA to mutate as it is passed to the next generation.  The birth dates are manufactured by me to indicate a 25 year generation.  In a few cases when the date of birth is known and it was near the 25 year mark, the actual date of birth as given in the Pedigree of Kelly is used. To highlight the life expectancy I have also listed some of the English Kings and Queens as their lives were often much better than the Irish of any standing.  The Kings and Queens of England were some of the most protected and cared for monarchs in the world.  King George II was at the time of his death in 1760 the longest living English Monarch and he died at the age of 77.  I think it is unreasonable to believe the regional kings of Ireland consistently lived longer or well into their 70s, 80s, or 90s when the Kings and Queens of England did not.  Certainly some may have lived to 80, those that did would be rare in number, and I doubt any lived to the age of 90.