Hi Ian, I don't believe that Jessie and Catherine are siblings of John and Archibald. No proof, but firstly I feel there is too big an age gap from John and Archibald Jr and secondly the age of the parents in 1841 puts the DOB for Archibald and Catherine at 1791 and 1796 in lieu of 1785 and 1791. I think it is a different family. John