I might just do a bit more research on the Dyce/Waddell part of the family during the summer, I had more or less abandoned them for a while as there were so many iligitimate births and they certainly didn't seem too bothered about which surname they used. I went for the more 'respectable' side of the family instead!! The Waddell connection is from an Anderson link. The Andersons went to Canada to live in the early 1900s (rather common name unfortunately)and I believe there are still direct decendents living there.
My Shiel(l)(s) link is from an iligitimate birth in Scotland but not via Christian Sheill, but linked to the Andersons.
Thanks for replying