SANFORD, FL – MARCH 25: Gwen Lawrence (L) and her granddaughter Kamari Sheppard attend a candelight vigil at a memorial to Trayvon Martin outside The Retreat at Twin Lakes community where Trayvon was shot and killed by George Michael Zimmerman while on neighborhood watch patrol on March 25, 2012 in Sanford, Florida. Participants planted a cross at the site to honor Martin. Rev. Jesse Jackson will lead a march in Sanford tomorrow. (Photo by Mario Tama/Getty Images)