Tory,
Would seem to be contemporary, but evidently not the same one.
The Rev. Ross Jebb, rector of Glenarm, m. at Connor 17 Oct. 1837 Fanny, dau. of the late William Maxwell of Fernisky and -- I think -- sister of William Maxwell junior, merchant. I have an idea the mother was also Fanny.
At about the same time Fanny's sister Jane m. Thomas Casement, attorney, of Ballee House near Ballymena. She d. 31 July 1839 at Glenarm, presumably while staying with her sister -- and possibly in childbed.
Ross Jebb d. at Glenavy 10 July 1851. Tom Casement and his 2nd wife Dora fostered the Jebb son Tommy (who I think was a godson) and when he left school sent him to Quebec to learn farming from Dora's cousin.
I'm afraid that's about all I know.