Cardinal Swynford's illegitimate daughter

Henry Beaufort (d.1447) was a son of John of Gaunt and Katherine Swynford, and was therefore a half-brother to King Henry IV. On the 14th July 1398 Henry was consecrated as Bishop of Lincoln, in November 1404 he became Bishop of Winchester and then in 1426 he was made a Cardinal by Pope Martin V. 

Henry Beaufort

In 1402 Henry fathered a daughter named Jane Beaufort. Many people gave her mother as Alice FitzAlan (1378-1415) however this is highly unlikely due to Jane's date of birth. It is possible that Jane was in fact named Joan, however due to non-standardized spelling it is unclear which it is. She may have been named Joan after Henry's sister. It does not appear that Jane was kept a secret or hidden away, as the Beaufort family themselves were an illegitimate line it appears they treated their children the same whether they were legitimate or not. 

Jane married Sir Edward Stradling (1389-1453, Acre) in about 1423. Edward was the eldest son of Sir William Stradling and Lady Isabel St Barbe. The ancient Stradling family was seated at St Donat's Castle in Glamorgan in Wales. Like his father and grandfather before him, Edward made a pilgrimage to the Holy Land to receive his knighthood in 1408.
The couple had four children;
+ Henry Stradling (1423-77, Cyprus) m. Elizabeth Herbert
                                                           + Thomas Stradling (1454-80) m. Janet Matthew
                                                           + Charles Stradling (b.1457)
                                                           + Jane Stradling (b.1459) m. Myles ap Harry
                                                           + Elizabeth Stradling (b.1461) m Richard Fleming
In 1449 Henry, his family and a servant were captured by the Breton pirate Colyn Dolphyn on their journey sailing from Wales to Somerset. The pirate held the family at St Malo while demanding a ransom of 2,200 marks. Sir Edward had to sell off  four of his manors to pay it; Sutton, Bassalleg, Rogerston and Tregwillim. Dolphyn finally released the family in 1451. A year later, Colyn Dolphyn returned to St Donat's and so the Stradlings lured the pirate to Nash Point, a sandbank, using false lights on the cliffs so as to capture him. Dolphyn was given a trial - although the legality of this is in question - and he was condemned to death. Colyn Dolphyn was buried up to his neck in the sand in Tresillian Cave. As his father did, Henry Stradling went on pilgrimage to the Holy Land in 1476. Henry was knighted at the Holy Sepulchre the following year. He died on his way back to England in 1477. He was buried in Famagusta in Cyprus.
+ Katherine Stradling m. Maurice Denys (1410-1503)
                                   + Walter Denys
                                   + John Denys
                                   + William Denys
                                  m2. Hugh Winston
+ John Stradling (b.1425). Had a daughter named Ann Danvers (b.1459)
It has been suggested by some that John joined the church and became Archdeacon of Llandaff in 1448, but later leaving Wales and obtaining the rectory of North Tawton in the diocese of Exeter in 1454.
+ David Stradling
The only mention of David was that he was the youngest child of the family and that he lived in Somerset, as he was very close to his mother.

It seems likely that Edward's appointment as Chamberlain of South Wales in December 1423 may have been a result of his new connection to the Bishop. He remained in this position until March 1437. Edward held a number of positions throughout the years; his rise furthered due to his connection to the royal family he had married into. 

November 8th 1424, Westminster
Grant, during pleasure, by advice of the council, to Edward Stradlyng, king's knight of the office of steward and receiver of the lordships of Cantreselly, Alsandreston and Penkethly, which are held of the earl of Hereford, the said office of steward and receiver of the kings lordships having been previously held as one office, with the fees of 40s. [a year].

July 31st 1432, Dogmersfield
Commission to Edward Stradelyng, knight, and William ap Thomas, knight, to enquire as to the malefactors who took at sea a ship called le George of Sluys laden with wines and honey of certain merchants of Flanders and Picardy, and brought her to the town of Dynby and sold the ship there with part of the wines and honey, giving the remainder to divers persons. The circumstances are to be ascertained and persons refusing to make restitution are to find. surety to appear in Chancery in the quinzaine of Michaelmas next.

April 28th 1434, Westminster
Commission to James Audeley, knight, Edward Stradlyng, knight, William ap Thomas, knight, Robert Grendour, knight, Thomas Arundell, knight, John Herle, knight, John Polryden and John Hunte, sarjeant at arms, to make inquisition touching a petition by Peter Preere, Richard Goulle, Francis Sarratt, William Lorget and their fellows, burgesses and merchants of the king's cities of Paris and Rouen, shewing that, whereas they recently laded two vessels of Rouen at Leseluse with goods worth 2,000 marks for the victualling of the said cities, these vessels were taken off Brumalet in Caux by certain of the king's lieges in two balingers of Wynchelse and Sandewyche and carried as if belonging to enemies to the parts of Cornwall and Wales, where they were disposed of. All goods whereof the petitioners can prove their ownership by the merchants' marks or otherwise are to be restored, or their value paid if they have been consumed, and any persons proving contumacious are to be brought before the king in chancery.

July 27th 1438, Dogmersfield
Appointment, during pleasure, of Edward Stradelyng knight, to be sheriff of Kermerdyn in South Wales, accounting at the exchequer of Kermerdyn.

When Cardinal Beaufort died in 1447, he mentioned both his daughter and son-in-law in his Will. 
In the original Will of Henry Beaufort, dated 20 January 1446;
"Item, I bequeath to Johanna, wife of Edward Stradling, Knight, two dozen dishes, four chargers, XII salt-cellars, etc and c li in gold". This bequest was the first one listed after the gift of a cup of gold to the king, Henry.
In the second codicil (2 September 1447) to Henry's Will is states;
"Item, I bequeath to Edward Stradling, Knight, a certain portion of silver vessels, according to the discretion of my executors"

Jane died in 1453, the same year as her husband.