Article continues below advertisementA retired FBI special agent said a tattoo on the arm of the masked suspect captured on the porch of Nancy Guthrie, the missing 84-year-old mother of Today co-anchor Savannah Guthrie, could help solve the baffling mystery of her disappearance.Former agent Jonathan Gilliam appeared on the Wednesday, March 18, episode of "The Megyn Kelly Show" to discuss a potential lead involving a tattoo in the investigation of the woman who was abducted from her Tucson, Ariz, home on February 1.