Left Out Doesn't Mean Not A Child

Just because someone is left out of an ancestor's will does not mean they were not the ancestor's child. They might have received property earlier or might have had a falling out with the parent and been left out of the will for that reason. 

Sometimes a will will mention the child and give them a dollar or a mere pittance so that they cannot say were left out, but that doesn't always happen. 

The 1850 era will of Thomas Chaney in Bedford County, Pennsylvania, only mentions a handful of his ten known children.