Sir Robert Spencer (afterwards second Earl of Sunderland) [q. v.] The marriage was a very happy one, but a quiet residence at Althorp was interrupted by the outbreak of the civil war, when Lord Spencer, though anxious for reforms, joined the king's party. In November 1642 Dorothy's third child, Penelope, was born, and in June 1643 Lord Spencer was created Earl of Sunderland; but in the following September he was mortally wounded at the battle of Newbury.
Shortly before his death he provided for his wife, the ‘dearest heart,’ by a jointure on his property, and settled 10,000l. on his elder daughter and 7,000l. on the younger one. A fortnight after the news of her loss had been broken to her, Lady Sunderland gave birth to a son, Henry, but this ‘sweet little boy’ died at the age of five. At her wish the Earl of Leicester was associated with her in the guardianship of her infant son, and for seven years she lived in seclusion at Penshurst with her father. After the execution of Charles I his children were placed for a time in Lord Leicester's care, and were treated with great kindness by the family. On her deathbed the Princess Elizabeth bequeathed sundry articles to Lady Sunderland.
In September 1650 Lady Sunderland left Penshurst for her son's house at Althorp, where for ten or twelve years she devoted herself to her children, and helped many distressed clergymen. Lloyd, in his ‘Memoirs of the Loyalists,’ says of her: ‘She is not to be mentioned without the highest honour in this catalogue of sufferers, to many of whom her house was a sanctuary, her interest a protection, her estate a maintenance, and the livings in her gift a preferment.’ She also effected many improvements at Althorp, and planned the great staircase of the house.
After a widowhood of nine years Lady Sunderland was married ‘out of pity,’ on 8 July 1652, to Robert (afterwards Sir Robert) Smythe of Sutton-at-Hone and Boundes in Kent, an old admirer and a connection of the family [see Smythe, Percy Clinton Sydney, sixth Viscount Strangford]. The wedding was celebrated at Penshurst, but Lord Leicester was not present. Smythe, who was an old college friend of Evelyn (Diary, 9 July 1652), is described by Dorothy Osborne as ‘a very fine gentleman’ who fully deserved his bride. The marriage turned out happily. One child, Robert, was born in 1653. At one time, perhaps after 1662, Lady Sunderland lived at Boundes, one of Smythe's houses, in sight of Penshurst. In 1658 Nathaniel Wanley [q. v.] dedicated to her his ‘Vox Dei, or the Great Duty of Self-Reflection on a Man's own Ways’ (Nichols, Lit. Anecd. i. 530); and in 1660 Dr. Thomas Pierce [q. v.], young Lord Sunderland's tutor, expressed his obligations in the dedication to ‘The Sinner impleaded in his own Court.’ After the Restoration a warrant was issued (14 Oct. 1662) for the payment of 1,000l. a year for five years to Lady Sunderland, in discharge of money lent by the late earl to Charles I; and in 1664 the countess was given the eighth part of profits in certain concealed waste lands, to be discovered at her own charge.
From 1663 to 1667 Lady Sunderland spent much of her time at Rufford, the seat of her son-in-law, George Savile (Lord Halifax). The two were always close friends, and Henry Savile, Lord Halifax's younger brother, was a frequent correspondent. After Lady Halifax's death in 1670, Lady Sunderland devoted herself to the care of Lady Halifax's four children. Her old admirer, Waller, was still among her friends, but, according to a well-known story, on her asking him when he intended to write more verses upon her, he replied, ‘When you are as young again, madam, and as handsome as you were then.’
In March 1679 Lady Sunderland had a serious attack of ague. Her letters to Lord Halifax in 1680 show that her sympathies were with him in the troubles connected with the Exclusion Bill, and that she hated the Earl of Shaftesbury, with whom her son, Lord Sunderland, was working. She died shortly after the execution of her brother, Algernon Sidney (7 Dec. 1683), and was buried on 25 Feb. 1684 in the chapel of the Spencers in Brington church, ‘in linen, for which the forfeiture was paid.’ There is no stone to mark her resting-place; but years afterwards Steele wrote in the ‘Tatler’ (No. 61): ‘The fine women they show me nowadays are at best but pretty girls to me, who have seen Sacharissa, when all the world repeated the poems she inspired.’ It is curious to note that on 29 March 1684 letters of administration were granted at the probate court of Canterbury to Lady Sunderland's creditor, John Benn, her sons, Lord Sunderland and Robert Smythe, having renounced. Robert Smythe, her only child by her second husband, married, before he was twenty, Catherine, daughter of Sir William Stafford of Blatherwick, Northamptonshire, and, settling on the family estates at Sutton-at-Hone, died in 1695.
Lady Sunderland was a favourite subject of Vandyck, whose paintings of her are to be found at Penshurst, Althorp, and Petworth.