Who's on first? Phrases like first "cousin, twice removed” confound the most ardent family researchers. Defining cousinhood and adding that “removed” phrase between two relatives is easy with this formula from the Texas State Library Genealogy Collection. 1. Find the ancestor common to two people. The common ancestor is “zero.” Then count down the generations to the subjects you are defining. 2. Subtract one from the smaller number of generations from the common ancestor. This establishes the cousin (first,second, etc.) relationship. 3 Subtract the smallernumber from the larger number (number being generations removed from the common ancestor) to yield "times removed.” Example: One subject is six generations,s removed from the common ancestor; another, four generations. Choose the smaller number, four, and subtract one to get three. They are “third cousins. Four from six Is two so they are twice” removed. Presto! Third cousins twice removed!