My long post has not reappeared, but will replace bit by bit. Frances you thoughts that Isabella Quirk age 42 is interesting is agreed by me so have spent time trying to find who she is. So I checked all Isabella marriages to Quirks 1818-1841 and found:
1821 William Quark to Isabella Collister Rushen
1822 William Quirk to Isabella Watterson Braddan
1823 Daniel Quark to Isabella Kelly Braddan
1823 Thomas Quirk to Isabella Fick Patrick
1824 William Quark to Isabella Cottier Braddan
1830 Nicholas Quirk to Isabella Garrett Braddan
1834 John Quirk to Isabella Keggin Rushen
1837 John Quirk to Isabella Sayle Marown.
Decided 1837 of Isabella Sayle best one to research first. They had three children to 1841 and were in Conchan Village. Isabella still in Onchan in 1851 but husband John , son John and son William are missing.
John snr buried Onchan 6/2/1949, John jnr buried 22/9/1849 aged 11 Onchan.
Found son William with uncle William Fayle ( Not Sayle) 43 unmarried, Aunt Mary 26 and Grandmother Isabella Fayle 70.
How many Williams and Isabellas are we going to find.
This cant be the Isabella we are looking for , will keep tracking them and we have to look at the Sayle / Fayle confusion and even include Fell.