Mary Erskine (b 1597), married at the age of 12, eldest daughter of
Sir John Douglas Erskine, 19th Earl of Mar, 2nd new Earl of Mar,
12th Lord Garioch, 7th Lord Erskine
(1556 – 14 Dec 1634)
by George Jameson
Her father-in-law, husband and two eldest sons were all Earls Marshal. Of the 10 Earls Marshall, there were 7 Williams, and 3 Georges. There were also two numbering systems – note that www.thepeerage.com uses the other system. So no possibility of confusion.