John Grant & Elizabeth Mackenzie

JOHN GRANT
[c1780- pre1855]
married
ELIZABETH MACKENZIE
[c1780-pre1855]
John Grant was known as John Clashnagrave, presumably because he came from there – Clashnagrave, Dornoch. A carpenter, and a crofter, he married Elizabeth (Betsy) Mackenzie circa 1802.
Elizabeth Mackenzie is the daughter of Colin Mackenzie and Barbara Gordon in Ardchu.
In 1834 John Grant paid two shillings to the fund collecting for a statue to the Duke of Sutherland.
The 1841 census shows John at Dalmore, Rogart, with his son George and daughter Barbara.
It would seem that both John Grant and Elizabeth Mackenzie had died pre 1851.
They had the following children:
BARBARA GRANT born 31 December 1803 Rogart (IGI) [died 19 April 1891 Culbuie, Lairg] [married John Mackenzie & John Ross] – 1841 census at Dalmore with father and her children William Mackenzie, born 1835 and Johanna, born 1838 - There was also a Sarah Mackenzie, aged 12 years – is this also a child of Barbara?– in 1851 Barbara was at Dalmore with her sister in law Christian Gunn
ROBERT GRANT born 20 March 1805 Rogart (IGI)
ELSPET GRANT born 12 December 1806 Rogart (IGI)
COLIN GRANT born 16 August 1808 Rovycraig, Rogart (OPR)
WILLIAM YOUNG GRANT born 5 April 1812 Rogart (IGI)
GEORGE URQUHART GRANT born 23 October 1815 Rogart (IGI) – with father at Dalmore in 1841 census
Can anyone tell me who the parents of John Grant were? I would also like to find death dates for John and Elizabeth.
Thanks.
Christine