This is part of the Seton descent to my son-in-law:
David Seton of Blackhall b. 1653 had an illegitimate son, mother unknown, David Seton, Baron Baillie I, born abt.1675. A Baron Baillie was not a title it was an office. David Seton of Blackhall later married Marjorie Archibald of Blackhall from whom he inherited lands. They had several children together including another David, Dr. David Seton born 1703. It appears that the illegitimate son David remained friends with his half siblings as he was a witness at several baptisms. This is all documented.
Illegitimate David Seton married Isabel Williamson. They had several children.
Their son Christopher Seton married Margaret Archibald; their son Dr. Christopher Seton married (1) Ann Laing (4 children) (2) sister Margaret Laing (Marian) (6 children). Dr. Christopher Seton son of Christopher and Margaret, married Ann MacAlpine a midwife. Christopher died in 1861 (I have his death certificate). After Christopher died Ann MacAlpine married a David Duncan. My son-in-law is descended from Christopher and Margaret's daughter Elizabeth Seton born 1838 in Pittenweem. Elizabeth Seton married a David Kinnear Cameron. However she had a son in 1858 before she married David Cameron, Alexander David Seton or Macgregor. Her daughter with David Cameron, Euphemia MacAlpine Cameron is my son in law's gt. gt. grandmother.
It is possible to go further back than I have shown here but space limits this. Let me know if you would like to access my Ancestry tree.
Rosemary Thorburn
Fife.