Well spotted with the will transcripts, Len! Especially as they take some finding listed amongst Cotteen/ Coteen/ Cotiam etc.
Megan, Isabella Cojeen's 1845 decree is at: www.iomfhs.im/lawsons/twill/1845_004.html and gives the name of her husband, and also those of their eight children including "Anne Cojeen wife of Charles Corkill" - which looks conclusive.
Husband James's will is at: www.iomfhs.im/lawsons/twill/1857_003.html
To see marriages and those bapts I mentioned previously you need to look at LDS films of the parish register copies. The films can be ordered to view worldwide for a small fee at any Family History Centre, or at the MM. See the 'phone book for the closest FHC, under "Church of Jesus Christ of Latter-Day Saints".
The LDS film number is at the bottom of the IGI record (FamilySearch.org) under "Source Call No".
For Charles & Ann's 1831 Lezayre marriage it is film no.0106727.
For their children's bapts in Ramsey it is LDS film no. 0106741 [1761-1849] which includes Esther.
To see records of the Cojeen family of Ballig in Lonan first get all the dates from extracted records in the IGI (extracted from the parish register) and then see LDS film no. 0106728 [1718-1878]
Eldest son and heir John appears to be under Cotjeen on the IGI, bapt 19 June 1816 Lonan, father James C., mother Isabella Kneal. Ann Cotteen bapt 15 March 1812 Lonan.
James Cotteen & Isabella Kneale married 8 Dec. 1810 Lezayre. This is on the same film as Charles & Ann's marriage, above [contains 1696-1848].