Sue,

Mary CORTEEN d/o Wm CORTEEN & Mary KERMEEN chr 1803 appears more likely

In the Maughold 1841 census she is living in the "Tallooqueen" household of Ewan KISSACK, who would have been her brother-in-law.

Her sister Catherine KISSACK (nee CORTEEN) having died in Jan 1841 in childbirth.

The connection increases the odds in favour of this individual.

The parentage of John KINRADE remains a mystery at this stage