***Smiles*** If you cannot go further back than about the 14th Century in your direct ancestors with Mary Stuart then your search will be fruitless. Because of my ancestors going way way back to 638AD then because of them also helping a good portion of the ancient royal families including King Arthur Pendragon then later King Richard I as well as his younger brother King John Lackland I as I have put in other threads here, I have a unique prospective.
Nor can my view point can be challenged since my ancestors had been chased out of Britain in 1621AD then founding USA by establishing Plymouth Colony Mass. By 1761 we left the USA to live finally in Nova Scotia, Canada where we reside today, I am the last of the "Brehenys" that no expert historian wants to document properly because perhaps I may be the last true heir to Queen Elizabeth IIs's throne and heir to Queen Gweniyiever's legacy of the Breheny-MacFergussons. So is history, that is mysterious.