A few corrections-
I believe the rest of the children either died or emigrated to USA as when Owen (the father) died everything was left to Eugene - which makes me think he was the only one left in Ireland - I might be wrong
Owen did NOT leave everything to his son Eugene- his will mentioned wife Margaret, sons Frank and Peter, daughter Annie McGilly, 'remaining sons.' Son Eugene applied for probate of the Will.
Probate of the Will of Owen Cullen late of Tullygarron County Armagh Farmer who died 27 November 1905 granted at Armagh to Eugene Cullen National School Teacher.
Click on "image" and you can view the full handwritten will.
What survives is a COPY of the Will written into the Will Book.