ROLAND L. WALKER, DEBORAH P. WALKER, llllllllllllllllllllllllllllllllllllllll Plaintiffs—Appellants, versus CSX TRANSPORTATION, INC., a Virginia Corporation, JOHN DOES 1–10, Georgia Residents, NORFOLK SOUTHERN RAILWAY COMPANY, a Virginia Corporation, NORFOLK SOUTHERN CORPORATION, a Virginia Corporation, llllllllllllllllllllllllllllllllllllllll Defendants—Appellees, UNILEVER BESTFOODS OF NORTH AMERICA, a Division of Conopco, Inc., a New York Corporation, llllllllllllllllllllllllllllllllllllllll Defendant.