She (Lucy Erskine) had an illegitimate relation with with Alexander 5th Earl of Moray's son John of Doune that was the father of Rev David Stuart.
David became an ordained Minister and was married to Harriet Jane Gibbons...which Jane hated the name Harriet as it sounded too closely with Harry!
I'm doing some heavy research on this and have found bits and pieces that relate to this....but documents and credible sources are slim to none as back then...unless high Nobility patents were involved....the female line was not very important back then! Sad to say...but it's more than likely true...
I am still digging and due to changing out systems I'm using it's hard to be on and keep up with this and housework repairs ...but I'll keep digging and trying to document this asap.