Thanks Len & Sue for those clues.

As you suggest, it appears Jane's first husband John COSTEAN/COSTAIN may have died circa 1811 and she married John BROOKBANK/BROCKBANK in Lezayre 07 Nov 1813.

The IGI has 3 offspring:
William 22 Nov 1814, Ramsey
John 11 Aug 1817, Ramsey
Jane 05 Mar 1820, Ramsey
prior to Jane BROOKBANK's burial at Maughold on 28 Oct 1822.

John BROOKBANK then appears to marry again to a Catherine CHRISTIAN in Lezayre 25 Jan 1823.

Thereafter the trail goes somewhat cold again as it appears the family may have left the Isle. There are no obvious burial records for them on the Isle and the children are not readily evident in the 1881 Census.

Thanks again, for the assistance.