I don't have a complete sequence of wills - there is an index to these on www.iomfhs.im which gives the mormon film ref (lookup Church of Latter Day Saints in phonebook to find nearest fam hist centre + borrow film) - I have summarised probably 20,000 (mostly 18th C)
Those I have give a partial picture (I'm still working on Jurby) the Mary in 1841 C is dau of Mary (the one who d 1808) - Mary senior is Mary Connally widow of John (they m Jurby 17510711) - her son Thomas is almost certainly the one who inherited - I don't think I have a will for Thomas but I suspect John is his son thus making the Mary his aunt.
The sequence of transfers of land ownership could be followed in lib vas and lib assed (look up these on manxnotebook)