I too have been researching a Campbell family who settled in the West Hawksbury region of Prescott adjacent to Lochiel. In that area known as the Ridge were MacLaurins and Lothiens. The all seemed to be connected and were mostly Baptists.
Here is the family who I am trying to follow but am dead ended at this generation.
The family of John Alexander Campbell and Ann McGill
John Alexander Campbell 1828 Baptist PEI
married Apr.14, 1873
Ann McGill Jan.06,1849 Catholic Vankleek Hill
John 1875 Vankleek Hill
Catherine 1878 Catholic Vankleek Hill
Francis Fredrick Dec.05,1879 Catholic Vankleek Hill
Daniel Apr.18,1882 Vankleek Hill
James Nov.23,1883 Vankleek Hill
Ann M Sep.23,1886 Vankleek Hill
Sarah J Apr.19,1887 Vankleek Hill
Earnest Jul.06,1889 Vankleek Hill
Christina Nov.18,1869 Vankleek Hill
Hilton Oct.10,1895 Vankleek Hill
You will note that John married a Catholic and children were raised as Catholics. John's mother was a MacLaurin who married an Alexander Campbell who emigrated from PEi where John was born.