Complex sentence: In 2004 she joined the United Daughters of the Confederacy through Thurmond's ancestry and documentation, and encouraged other African Americans to do the same, to enlarge the lineage societies' sense of history.
Split into simpler sentences: In 2004 she joined the United Daughters of the Confederacy through Thurmond's ancestral lines. She encouraged other African Americans to do the same, to enlarge the lineage societies' sense of history.