Charles Thomson was the Founding Father who served as secretary of the Continental Congress during its 15 years.  Along with John Hancock, his signature graced the first draft of the Declaration of Independence.  Thomson also designed the Great Seal of the United States.  After his initial burial at the family homestead Harriton in Bryn Mawr, his remains were transferred to Laurel Hill. 

Thomas McKean served multiple roles in colonial days – president of Delaware, Chief Justice of the Pennsylvania Supreme Court, President of the United States Congress, and Governor of Pennsylvania, among others.  Although his efforts in 1776 were what made the Declaration unanimous, he was the last man to sign that historic document.

Thomas Leiper was a successful tobacco importer who built the first railroad in Pennsylvania on his property at Nether Township.  As a founding member of the First City Troop, he fought with the Patriots at the Battles of Princeton, Trenton, Germantown, and Brandywine.  His personal wealth helped to subsidize the siege of Yorktown.  He and Thomas Jefferson exchanged hundreds of letters. 

All three of these men died before Laurel Hill opened in 1836, but they were all friends of Thomas Jefferson who eventually ended up at Laurel Hill Cemetery. 

I did the research on Thomson & McKean, while the script for Thomas Leiper was written by fellow tour guide Peter Howell.