Avis/Avie Garnett

William Andrews and wife Avis/Avie/Ava were my ancestors.There is a lot of confused information on the internet because there were several Andrews-Garnett marriages, and people have confused the couples married, they have estimated ages incorrectly, etc.
I am not an expert on the Andrews, but was told by Andrews researchers that the Avis Garnett born 9 or 19 July 1725 (1731 some say) married Mark Andrews, nephew of my William Andrews who married (her aunt?)Avis Garnett, born about 1700.

William Andrews and Avis (Garnett?, believed to be the daughter of Thomas Garnett and Elizabeth Muscoe) had a son William Andrews born about 1725 who married Ann (Brooks Varney?) and had Ephraim, David, Varney, William, Ann/Nancy Andrews (m. Capt. John Floyd) and others.