On April 20 1663, married James Scott http://www.pepysdiary.com/encyclopedia/5315/ the illegitimate son of the King http://www.pepysdiary.com/encyclopedia/344/ and Lucy Walter http://www.pepysdiary.com/encyclopedia/5743/ . She was 12 years old when she married the 13 year old Scott.
From Grammont's footnotes
This was Lady Anne Scott, daughter and sole heir of Francis, Earl of Buccleugh, only son and heir of Walter, Lord Scott, created Earl of Buccleugh in 1619. On their marriage the duke took the surname of Scott, and he and his lady were created Duke and Duchess of Buccleugh, Earl and Countess of Dalkeith, Baron and Baroness of Whitchester and Ashdale, in Scotland, by letters patent, dated April 20th, 1673. Also, two days after he was installed at Windsor, the king and queen, the Duke of York, and most of the court being present. The next day, being St. George's day, his majesty solemnized it with a royal feast, and entertained the knights companions in St. George's hall in the castle of Windsor. Though there were several children of this marriage, it does not appear to have been a happy one; the duke, without concealment, attaching himself to Lady Harriet Wentworth, whom, with his dying breath, he declared he considered as his only wife in the sight of God. The duchess, in May, 1688, took to her second husband Charles, Lord Cornwallis. She died Feb. 6, 1731-2, in the 81st year of her age, and was buried at Dalkeith, in Scotland. Our author is not more correct about figures than he avows himself to be in the arrangement of facts and dates: the duchess's fortune was much greater than he has stated it to have been.
http://www.pseudopodium.org/repress/grammont/no... see note 157
Chart showing the number of references in each month of the diary’s entries.