I am tracking Robertsons in Granville Co NC, and ended up looking at Brunswick Co. records, and further at two related Chancery Court cases in the 1780s by John Robertson & Wife, and Nicholas Robertson & wife, complainants against the executors of William Short's will, which provided that after his widow's death that the portion he left to her be divided equally amongst his children.The will, as you know does not name the daughters, however the Chancery Court case does (god bless executors and administrators that don't disburse quickly!).
The two separate cases make clear that daughter ALICE was the wife of Charles Abernathy, daughter ELIZABETH was the wife of John ROBERTSON, and that daughter TABITHA was the wife of Nicholas ROBERTSON.According to Robertson researchers William Short, d. 1769 or so, was married to Sarah ROBERTSON, who could be sister of both Nicholas and John.Also, by 1780s, William Short Jr., brother of the three daughters, was deceased and his wife was named Elizabeth.
The Chancery Court files are quite short and otherwise unremarkable.The originals are at the Library of Virginia (not microfilmed), and I encountered them at the LVA website which has indexed these records for some counties.
Should you wish to view them yourself the references are: