In an New York Law Journal article, Terence Smolev explains:
Increasingly disputes among family members take place regarding the disposition of assets of a deceased person. These disputes over the past 20 or more years have increased due to changes in demographics of families. It is not unusual to find families with multiple marriages of a deceased and/or children from these multiple marriages. As a result, in-fighting amongst the various family members takes place in both wills and administration proceedings.
The full text of the article may be viewed here: Changing Family Demographics