the castle herself on her father's death Marriages and issue Margaret married firstly, about 1335, John Segrave, 4th Baron Segrave, by whom she had two sons and two daughters: John de Segrave, who died young. John de Segrave (d. before 1 April 1353), second of that name, who was contracted to marry Blanche of Lancaster, younger daughter and coheiress of Henry of Grosmont, 1st Duke of Lancaster. However, the contract was later declared void and Blanche later married John of Gaunt. About 1349, a double marriage was solemnized in which John Segrave married Blanche Mowbray, while John's sister, Elizabeth Segrave, married Blanche Mowbray's brother, John de Mowbray, 4th Baron Mowbray, Pope Clement VI having granted dispensations for the marriages at the request of Lancaster, in order to prevent 'disputes between the parents', who were neighbours. Elizabeth de Segrave, 5th Baroness Segrave, who married John de Mowbray, 4th Baron Mowbray. Margaret de Segrave, who died young, before 1353. Shortly before 30 May 1354, Margaret married secondly, and without the King's license, Sir Walter de Manny, 1st Baron Manny, by whom she had a son and two daughters: Thomas Manny, who drowned in a well at Deptford at the age of five. Anne Manny, 2nd Baroness Manny, who married John Hastings, 2nd Earl of Pembroke. They had one son, John Hastings, 3rd Earl of Pembroke (29 August 1347 – 16 April 1375), who married firstly Elizabeth of Lancaster, the daughter of John of Gaunt, Duke of Lancaster, in 1380, with no issue; and secondly, Philippa Mortimer, daughter of Edmund Mortimer, 3rd Earl of March, with no issue. He died at the age of 17 in a jousting accident. Upon his death, the Earldom of Pembroke and the Barony of Manny became extinct, while the Barony of Hastings passed to his cousin, John Hastings, 6th Baron Hastings. Isabel Manny, who was living in 1358, but died without issue before 30 November 1371. Distinction As her brother had died without issue, she succeeded to the earldom of Norfolk and the office of Earl Marshal at her father's death in 1338. To date, she is the only woman to have held the latter office. Fictional representations Margaret is a character in Georgette Heyer's last novel My Lord John, where she is portrayed sympathetically as a kindly though outwardly formidable old lady. She is saddened by the death of so many of her children and grandchildren,