Complex sentence: They celebrated their 65th wedding anniversary in July 2011, making them the second-longest wed Presidential couple after George and Barbara Bush, a position they have held since passing John and Abigail Adams on July 10,2000.
Split into simpler sentences: They celebrated their 65th wedding anniversary in July 2011, making them the second-longest wed Presidential couple after George and Barbara Bush. Prior to this milestone, their long-term marriage surpassed that of John and Abigail Adams on July 10,2000.