Hiya Sharon and a warm welcome to Rootschat
one possibility - that's if John was born in Campbelltown -
Name John Mc Murchy
Gender Male
Christening Date 07 Mar 1762
Christening Place CAMPBELTOWN,ARGYLL,SCOTLAND
Birth Date 04 Mar 1762
Father's Name William Mc Murchy
Mother's Name Mary Wilson
make a note of it in case it IS your John - I will see if there is also a Thomas ??
Isobel McMurchey - baptised 31st August - born 27th August 1760 Campbelltown father William / mother Mary Wilson ....
Mary McMurchey born 4th Jan 1768 baptised 7th Jan 1768 - same abode and parents
Jean - b 14th June 1765 / bap 16th jun 1765 - same abode / parents
John 1762
Margaret 1768
these may be too old - if you say William was born 1720 - it makes him 39 / 40 at the first born ??
anyway 5 kids for William McMurchey and Mary Wilson ....probably related - but COULD be your William in Campbelltown .
ALL those baptisms are on
www.familysearch.org