Roby's name is given in one entry as Robena. Probably her middle name was Soule (or Sowle), after her maternal grandmother.
The death record identifies her parents as Jeremiah Manchester and Mary Dennis.
Her grave is next to her husband's and daughter's, behind a farm across from 330 King Street, Tiverton. I have visited the graveyard and have a photo of the gravestone.
From the RI Cemetery Database: ROUNDS, ROBY S 1832c - 12 FEB 1899 TV033