Hi Kit,
I think you have the correct marriage for Christian, I have found the correct one for Margaret, I think.
James Laverock married Margaret Cockburn 23 May 1735 in Wemyss, Fife (Extracted record on IGI)
They had the following children, all extracted records on IGI,
Peter Laverock b 20 Oct 1737 bap 23 Oct 1737 Wemyss, Fife
James Laverock b 14 Jan 1739 bap 21 Jan 1739 Wemyss, Fife
William Laverock b 03 Jan 1741 bap 04 Jan 1741 Wemyss, Fife
Tom