Don't know if you have received info on these two individuals yet but I will include what I have on them.These two do not appear to be a part of my Gleaves/Glaves line but I did some research on them to find out if there was a connection.I don't believe any of my lines were in SC during this period.The only info I have on them comes from census records which you may have already researched.
Here's what I have, hope it helps.
Nancy C. Gleave first appears in the 1860 Columbia, South Carolina Census.She states that she is 26 years old which would have her born about 1834.Her place of birth is not listed.Also listed are what appear to be her children; Thomas W. (8),Maragret E. (6), Andey G. (4) and William M. (2).Nancy and the children are living in the household of a woman named Margaret Miles.This could be her mother but there is no evidence to confirm this.Margaret is 69 and states that she was born in Maryland.There is no record of Nancy's husband. In 1870 Census, Nancy is found in the same location, Ward No. 1, Columbia.In this instance, her married name is listed as Gleaves.She is 36 and states she was born in SC.She owns real estate valued at $1,000 and personal property worth $550.Margaret E. (16) and William M (12) Gleaves are also listed.Both children are listed as being born in SC.Margaret Miles, age 80 is also living with her.This time Margaret is listed as being born in SC as well.One additional individual is also listed; Bernard Cavanaugh, a 26 year old machinists from New York is living with Nancy's family.If there is any relationship to Nancy, it is not listed. In 1880 Nancy C. Gleave is still living in the first Ward.She states she is 44 years old and is a widow.She lists her birthplace as well as here parents as South Carolina.William M. Gleave, now 21, appears in the same household.He lists his occupation as "Keeps Shop".He is single, born in SC and lists his father as being born in England.Daughter Margaret has married a man named Samuel Reasoner and they have four children.This family lives with Nancy as well.Margaret also states that her father was born in England. N.C. Gleave is listed in the 1900 census still living in Columbia.She is living alone and states that she is 63 years old and was born in June of 1836.She further states that she was the mother of six children, only one of which was still living.This would be daughter Margaret Reasoner, who is living next door with her family.Nancy further states that she can read, write and speaks english. Going back to the 1850 census, there is no record of a Nancy Gleave(s) or Nancy Miles in SC.The only entry with the surname of Gleave appears in the records of St Michael and St Phillip parishes, Charleston, SC.A tavern keeper named Thomas Gleave is listed.He would have been born about 1818 and he states his birth occurred in England.It appears that he is single at this time.Thomas does not appear in SC census records before or after 1850. If Thomas was Nancy's husband, he would have died between 1857 and 1860.