Hi there I also come from a family of Jack's whose ancestry reaches back to Avoch, Scotland. My ggrandfather Henry and 2 of his brothers, William and Robert decided to add an 's' to the end of their surname and this has caused confusion. My ggrandfather and his siblings all were born in or around the london/walthamstow area. Amy a sister of theirs was born in Bolan Green. Other sisters were Annie and Loure. There were about 12 children in all but I don't know all of their names. I have a little info on my ggrandfather and am willing to share.