The Bob L. Plunkett Family

I am searching for Plunkett and Murdock,they lived in Newberry, South Carolina, Newton County, Georgia, Haralson County, Georgia and DeKalb and Cherokee County, Alabama. Elizabeth Ann Plunket married David Murdock and Margaret Catherine Plunket married John Wesley Murdock. Surely some of the descendants of Elizabeth and Margaret would know the maiden names of these two Plunket girl's Mothers. Their fathers name was James Plunkett as noted below.

James Plunket born on March 21, 1795 is my great-great grandfather. I would like to know the names of his parents. He was born in Newberry County, South Carolina. He married Nancy Cleland his first wife and then moved to Newton County,Georgia in 1829 and Nancy died near that date, he then married Rebecca L. maiden name unknown, Rebecca had three children,one of whom was my great grandfather, William Thomas Plunket. Rebecca died in 1846 and James married for the third time to Martha Ann Johnson in Newton County, Geogria and in 1856 they moved to Cherokee County, Alabama and James died there in 1872. William Thomas Plunkett married Nancy Nave in 1857 and they had several children one of which was my grandfather, William J. Plunkett born February 10, 1872. He married Sarah Louisa Pugh in 1902 in Pauls Valley, Oklahoma. They had four children that lived until adulthood. My father, Gip Dowdy Plunkett was born on November 16, 1909 in Hollis, Oklahoma. He married my mother, Iva Mae Witt on June 10, 1927 in Amarillo, Texas. I was born on June 24, 1931 in Yates, New Mexico. I now live in Japan and have lived here for the past 15 years. I have considerable information on the Nave's, Siniard's, Witt's, Pugh's, Durham's, Starne's and Plunkett's.