interesting problem - Wm and mary would appear to be in Peel in 1841 (staying with Thos Corkan - wm describes himself as farmer) - they had been married a month and would appear to be visiting Mary's parents who lived next door.
Judging from 1851 when he is at Ballakerka as proprietor with is mother next door (jane kelly widow of Patrick who died 1839 - MI in Patrick (old yard #78) - In memory of/ PATRICK WATTERSON/ of Ballakakay/ who died 1st January 1839/ aged 57 years/ also/ WILLIAM WATTERSON/ of Ballakakay/ who died 1st Jan 1878/aged 82 years.

wm in 1851 would appear by age + birth parish to be s/o Jane + patrick bapt Patrick 18150702 but this seems to need more explanation of who the Wm in the MI is
Patrick would appear to be s/o Patrick Watterson + isabel Keigh bapt Pat 17820224 + eldest son thus inherited land (land records will help trace back - Ballakerky is near Glenmaye)

Mary is probably d/o philip kewin + ann quayle bapt German 18161215