My Mother's cousin did extensive research on the Garrett family. My Mother is a Garrett from the Elijah Garrett line. I found two Cobbs mentioned. Elijah (Isaac Garrett's son) was married three times. First wife, Celia Jane Clark. Second wife, Melvina Cobb (married October 18,1885). Third wife, Burcelia Cobb (married April 3, 1898). He was born on September 6, 1846 in Overton Co. TN. and died April 12, 1916. The book does not mention if the women were sisters. My Garrett's came from Buckingham County, VA. Hope this helps!