1851 in Arbory at Ballakindry:-

Margaret Quilliam widow age 75 on 18 acre farm born Arbory
William .. son 30 farm labr. Arbory
Anne .. wife 24 Marown
James .. son 4 Marown Listed in IGI as Gain (Cain)
Thomas .. son 1 Arbory

William and Anne were married in Marown 14 July 1849 hence the name cain for James.

IGI lists:-
Thomas 1850 son of William and Anne Quilliam
Jane 1852 ( yours I presume)
Anne 1852 ( looks like Janes twin)
William 1854
Thomas 1857 ( the first one died age 4)
Catherine 1859
Eleanor Elizabeth 1861
John 1865
Charles 1866
Evaline 1869
Clara 1872

At this point see Brian Lawsons site www.lawsons.ca to calculate some of the deaths. He has listed Arbory (arb).

1881 shows:-

Ann widow at Ronague ( I think William died 1878 )
Eleanor 18
John 16
Evan 12 (presume Eveline)
Clara 9
Lawrence 3 Grandson ( a Quilliam but can't find which parent)

Len Faragher