For those interested in the most famous of the Scots/Irish Families I recommend that you try and get hold of a copy of a book called "Castle Caldwell and Its Families" by John B Cunningham of Belleek.
Copies may be obtained from the author at Commons, Belleek, Co Fermanagh or Mr T McMahon No 6 Tully, Monaghan, Co Monaghan or from Mr David Hall, Darling Street, Enniskillen, Co Fermanagh.
This is a comprehensive history of the Caldwell and Blennerhasset families of Castle Caldwell of 210 pages including index. It is a rollicking tale in places and there are gaps but otherwise it is a serious and well-researched work and Mr Cunningham is to be congralulated for his efforts. I believe that it was published about 1980.
I have tried to construct a family tree from the iformation in the book and it works - to a point. Mr Cunningham seems to indicate the family died out. From what I have seen this family had many descendents throughout Ireland - England - the USA and Canada. He indicates one member of the family married a Portuguese lady and settled in Brazil.
None of the family seem to have returned to Scotland.
He does saythat the eldest son of Willliam Caldwell of Straiton was named John and was born at Prestwick firstly married to Janet Grier and secondly married to Mary Swetenham. The son by his first marriage - John Caldwell "disappears" after testifying to his father's death on 19/2/1639. The family that rose to a position of wealth and power on the back of the Irish troubles came from the second family.
John Cunningham mentions quite a few ancient Scots Caldwell's but he doesn't try and link them o William of Straiton.
Incidently Prestwick is now the site of a large airport near Ayr and on the other side is St Quivox where my ancestry springs from circa 1750. I don't think that I am descended from William of Straiton - I think our ancestral home was the Kilmarnock - Ayr - Irvine triangle.