related.ll -- by Eugene Reimer 2010-February

related.ll is a Lifelines program to show all the ways two individuals are related (genetically), and their Relatedness (as defined by Sewall Wright) which is the expected fraction of their DNA that's identical by descent; for example, parent and child have relatedness 0.5, grandparent and grandchild 0.25, half-siblings 0.25, full-siblings 0.5.  A more complete description, and examples of its output, are found in my genealogy page.  Lifelines is available from

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