(2.) Agnes Ross (perhaps by first wife), married Duncan Campbell of Boath.
References
The Scottish Antiquary: Or, Northern Notes & Queries, Volumes 3-4. “Line of Balnogown.” Page 10. GoogleBooks
https://www.greatclanross.org/htext6.html Alexander Ross, 9th of Balnogowan, by his marriage to Janet, the daughter of the third Earl of Caithness, produced six offspring: (1) Robert; (2) Hector; (3) George, who became the tenth of Balnagowan; (4) Catherine, who was the second wife of Robert Munro of Foulis, and was tried for witchcraft; (5) Agnes and (6) Christian, who married Kenneth MacKenzie third of Dochmaluak.