I have some Wilkinson connections and did some work before - excuse teh stream of conscious below ...
Church baptisms:
Richard Wilkinson b27 May 1838 Kilcoole, Delgany, Wicklow to John Wilkinson (lawyer) & Hanah ?
Also the 1824 Richard from previous post in Wexford
1829 well before church records in a lot of parishes.
According to Tithe Applotments, the only recorded one in Wicklow is
John R Wilkinson in Ballintemple Wicklow in 1824 - this is near Avoca village and not Delgany. As a lawyer, Delgany John may not have been a tenant.
Several in Wexford
By Griffith Valuation in 1853
http://www.askaboutireland.ie/griffith-valuation/index.xml?action=doNameSearch&familyname=Wilkinson&firstname=&offset=0&countyname=WICKLOW&parishname=&unionname=&baronyname=&totalrows=21&PlaceID=0&wildcard=Wilkinson heads of household in Co Wicklow in following parishes:
Kilcoole (Richard), Kilpoole, Glenealy, Newcastle (2, including another Richard) & Rathnew. In Kilcoole the Richard was subletting to other tenants.
My guess is Hadden should be Madden. There was several Madden families in Wicklow for the Griffith valuation (1850s) including a Jane in Rathnew (suggesting family name).
John Wilkinson married Sarah Elliss in Newcastle 1834
A Jane Madden married Patrick Smullen Bray 1825