The Staffords were a fairly minor noble family of the Midlands who rose to great prominence after Sir Ralph Stafford abducted the great heiress Margaret Audley in early 1336.
Ralph was the son and heir of Edmund Stafford (b. 1273), and was born in 'Amynton', i.e. Amington, near Tamworth in Staffordshire, on 24 September 1301. The writ to hold his proof of age was issued on 10 May 1322, though it didn't take place until 6 April 1323, and the record of it is defaced and not terribly informative. Ralph, now twenty-two, was granted his lands on 6 December 1323, Edward II having taken his homage.  Ralph's mother was Margaret Basset, sister of Ralph, Lord Basset of Drayton (d. 1343), and presumably Ralph Stafford was named after his maternal uncle. A few decades later, the Staffords would become the heirs of the Bassets of Drayton because of this marriage; see below.
Edmund Stafford died before 12 July 1308 when his eldest son was not yet seven years old. On that date, there's a reference on the Fine Roll to "Margaret, late the wife of Edmund, baron of Stafford", and Edward II granted the rights to her second marriage to her brother Ralph Basset of Drayton for 100 marks (£66).  By 26 August 1308, Margaret Stafford née Basset had married her second husband Thomas Pype without permission from the king or her brother, and Edward II confiscated their lands.  Thomas Pype, Margaret, her sons Ralph Stafford and his younger brother Richard, and several others named Pype and Stafford were "indicted for unlawful assemblies, alliances and confederations" before April 1326.  Margaret died on 17 March 1337. Her dower lands from her marriage to the long-dead Edmund Stafford passed to her eldest son Ralph, said in April 1337, incorrectly, to be either "40 years on 17 March last" or "30 years and more at the feast of St Denis last" (the feast of St Denis is 9 October). 
Ralph Stafford married Katherine Hastang or Hastings before 9 February 1327.  I'm afraid I know nothing at all about her. They had two daughters, Joan and Margaret Stafford, both of whom had children with their respective husbands Nicholas Beke and John Stafford of Bramshill. Katherine Stafford née Hastang died sometime before early 1336 when Ralph Stafford abducted the great heiress Margaret Audley from her home in Thaxted, Essex, and married her. In May 1332, Ralph had been in the retinue of his future parents-in-law Hugh Audley, later earl of Gloucester, and his wife Margaret de Clare, when they accompanied Edward III's teenage sister Eleanor of Woodstock, Margaret de Clare's much younger first cousin, to her wedding in Nijmegen. 
Ralph and Margaret Audley's first son, Ralph Stafford junior, was born sometime before 16 March 1339, probably not too long before.  Their younger son and ultimate heir, Hugh Stafford, must have been named in honour of his paternal grandfather Hugh Audley, earl of Gloucester, and was born between about 1342 and 1346; he was somewhere between twenty-six and thirty years old in the autumn of 1372.  They also had four daughters, of whom three married and had children: Elizabeth married Fulk Lestrange of Blackmere, John, Lord Ferrers of Chartley, and Sir Reynold Cobham; Joan married John, Lord Charlton of Powys; and Beatrice married Maurice FitzGerald, earl of Desmond, and Thomas, Lord Ros. Ralph Stafford also fathered an illegitimate son named Thomas Stafford during his marriage to Margaret Audley. In 1364, Thomas's legitimate half-brother Hugh Stafford petitioned the pope on Thomas's behalf; he was joining the Church, and was granted a dispensation to be ordained and hold a benefice. Hugh called him 'his brother Thomas de Stafford, illegitimate son of a married man'.  Margaret Audley died in 1349, aged about twenty-seven; her widower and abductor outlived her by nearly a quarter of a century.
Little Ralph Stafford, born before 16 March 1339, was married on 30 November 1344 to Maud of Lancaster, born on 4 April 1340 as the elder daughter of Henry of Grosmont, earl of Derby, and the granddaughter of Henry of Lancaster, earl of Lancaster and Leicester.  Maud was four years old at the time of her wedding and Ralph was about five or six. In 1344, Henry of Grosmont and his wife Isabella Beaumont had two daughters, Maud and Blanche, aged four and two, and Henry surely anticipated having a son who would be his heir. A couple of years later, he arranged a marriage for his younger daughter Blanche with John Segrave, heir to his father Lord Segrave and his mother Margaret of Norfolk. In later years when he realised that his daughters would be the Lancastrian heirs, Henry arranged greater marriages for them: Maud married secondly Wilhelm, duke of Bavaria, son of the Holy Roman Emperor Ludwig of Bavaria, and Blanche married Edward III's son John of Gaunt. Young Ralph Stafford was dead by November 1347 when the inquisition post mortem of his maternal grandfather Hugh Audley was held (and as it happened, young John Segrave, who would have married young Ralph's sister-in-law Blanche of Lancaster, also died as a child, in or before 1353).  If little Ralph had lived, and assuming that he and Maud of Lancaster had children together, the Stafford family would have come into half of the vast Lancastrian inheritance on Henry of Grosmont's death in 1361.
Ralph Stafford was made the first earl of Stafford in 1351, and died on 31 August 1372 at the age of almost seventy-one. His heir was his only surviving legitimate son Hugh Stafford, aged somewhere between twenty-six and thirty when Ralph's inquisition post mortem was held. Hugh, second earl of Stafford, married Philippa Beauchamp, daughter of Thomas Beauchamp, earl of Warwick (d. 1369) and granddaughter of Roger Mortimer, first earl of March (d. 1330) around 1 March 1351 when he was somewhere between five and nine years old.  I assume Philippa was around the same age; she was one of sixteen children, and her brother Thomas Beauchamp, their parents' second son and heir, was born about 1338/39. Hugh and Philippa had five sons and three daughters. Their daughter Joan (d. 1442) married Richard II's half-nephew Thomas Holland, earl of Kent and duke of Surrey (d. 1400); their daughter Margaret (d. 1396) married Ralph Neville, later earl of Westmorland (d. 1425); and their daughter Katherine (d. 1419) married Michael de la Pole, earl of Suffolk (d. 1415).
Hugh and Philippa's eldest son was named Ralph after his paternal grandfather, and was murdered by Richard II's half-brother Sir John Holland in the summer of 1385 when he was in his late teens or thereabouts. The shock of their eldest son's murder perhaps hastened Earl Hugh's death: he died on the island of Rhodes sometime between late September and mid-October 1386 (his wife Philippa had died sometime before April 1385). On the other hand, Hugh made his will on 6 April 1385, which suggests that he had been ill for some time, and in it he raised the possibility of his dying outside England, so had perhaps already planned a pilgrimage even before Ralph's murder. He added a codicil to the will on 25 September 1385, on Rhodes.  His daughters Margaret and Katherine were already married in 1385, and he called them Margaret de Nevill and Katherine de la Pole. Joan Stafford was not yet married and must have been his youngest daughter - she outlived all her siblings by decades and did not die until 1442 - and Hugh added his wish that she "be well and fitly married". He also left bequests to his four younger sons, Thomas, William, Edmund and Hugh; when the earl made his will, his eldest son Ralph was still alive and was his heir to the large Stafford inheritance, so was not left any money or goods by his father.
The Stafford heir in 1386/87 was Hugh and Philippa's second son Thomas, born around 25 March 1369; he was "18 years on the feast of the Annunciation, 10 Richard II". Thomas Stafford was also heir in 1390 to Sir Ralph Basset of Drayton: "Thomas earl of Stafford, aged 21 years and more, son of Hugh son of Ralph likewise earl son of Margaret sister of Ralph father of Ralph his father is his next heir".  Thomas married Edward III's granddaughter Anne of Gloucester in c. 1390. Born a little before 6 May 1383, she was a young child at the time, and was the eldest daughter of Edward III's youngest son Thomas of Woodstock, made duke of Gloucester in 1385, and the great heiress Eleanor de Bohun, countess of Essex. Anne had an older brother Humphrey and younger sisters Joan and Isabel, but Humphrey and Joan died as teenagers and Isabel became a nun at the house of the Minoresses in London, and Anne became her parents' sole heir and carried her half of the de Bohun inheritance to the Staffords.
Thomas Stafford died on 4 July 1392, at the age of twenty-three; he of course left no legitimate children, as Anne of Gloucester was still far too young for the marriage to have been consummated. His heir was his next eldest brother, Hugh Stafford and Philippa Beauchamp's third son William Stafford, born on 22 September 1377. William himself died on 6 April 1395, aged seventeen, leaving the fourth brother, Edmund, as the Stafford heir. Edmund was said to be seventeen in November 1395, so was apparently not much younger than William. He was granted his full inheritance on 23 March 1399 even though "Edmund is found not of full age".  Not long before 28 June 1398, Edmund Stafford married his former sister-in-law Anne of Gloucester without royal licence, and their son and heir Humphrey, presumably named in honour of his maternal uncle Humphrey of Gloucester (1382-99) and Anne's maternal grandfather Humphrey de Bohun, earl of Hereford, Essex and Northampton (1342-73), was born on 15 August 1402.  Less than a year later Edmund was killed at the battle of Shrewsbury, fighting for Henry IV against the Percys. Humphrey Stafford, heir of the Staffords and to his mother Anne's share of the de Bohun lands, became the first duke of Buckingham, and was the grandfather of Henry Stafford, executed by Richard III in 1483, and the great-grandfather of Edward Stafford, executed by Henry VIII in 1521. The fifth and youngest son of Hugh Stafford and Philippa Beauchamp was Hugh, who died childless on 25 October 1420; his nephew Humphrey was his heir, the five Stafford brothers having fathered only son beween them.  Edmund Stafford and Anne of Gloucester (d. 1438) were also the parents of Anne Stafford (d. 1432), countess of March and Ulster by her first marriage and countess of Huntingdon by her second.
1) Calendar of Inquisitions Post Mortem 1317-27, no. 354; Calendar of Close Rolls 1323-27, pp. 60-61, 291.
2) Calendar of Fine Rolls 1307-19, p. 26; CIPM 1307-17, no. 131.
3) CCR 1307-13, p. 76.
4) CCR 1323-27, p. 467.
5) CIPM 1336-46, no. 126.
6) Calendar of Patent Rolls 1327-30, p. 7.
7) CPR 1330-34, p. 276.
8) CPR 1338-40, p. 213.
9) CIPM 1370-73, no. 210.
10) Petitions to the Pope 1342-1419, p. 491.
11) Knighton's Chronicle, ed. G. H. Martin, vol. 2, p. 30; The National Archives DL 27/36.
12) CIPM 1347-52, no. 56.
13) CPR 1350-54, p. 50.
14) Testamenta Vetusta, vol. 1, pp. 118-20.
15) CIPM 1384-92, nos. 432-54, 963-75.
16) CIPM 1392-99, nos. 196-239, 556-7; CPR 1396-99, p. 456; CCR 1396-99, p. 467.
17) CPR 1396-99, pp. 376, 384; TNA SC 8/221/11020; CIPM 1422-27, no. 369.
18) CIPM 1422-27, nos. 98-101.