While doing some research for a blog post last night, I looked up the entry for Thomas Grey, first Marquess of Dorset, in W. E. Hampton's Memorials of the Wars of the Roses. This book, put out by the Richard III Society in 1979, contains descriptions of memorials and tombs connected to various Wars of the Roses personages, with a potted biography of each one. Though most of the biographies are fairly straightforward, Hampton's account of Dorset, Elizabeth Woodville's eldest son by her first marriage, is a rather different affair.
After a more or less factual recounting of Dorset's life, Hampton suddenly changes tack and launches into an account of Dorset's supposed sexual exploits with his female wards, the daughters of John Neville, Marquess Montagu. He writes that Dorset appears to have fathered a bastard daughter on Elizabeth Neville, Lady Scrope of Masham, though Hampton rather damages his case by noting that the father could have been Dorset's son instead. (Dorset senior, Dorset junior, what's the difference?) Hampton then moves to the case of Anne Neville, married to Sir William Stonor. "The marriage took place at the end of 1481, and almost immediately afterwards she rode to join the Marquis in Taunton Castle. She wrote from there to Stonor in February, 1482, having, as she says, been with the Marquess longer than anticipated. In August she presented Stonor with a son . . ."
By this, Hampton apparently is implying that while Anne was staying with Dorset, he took the opportunity to father a child upon her, which was passed off as Stonor's. Aside from the fact that there's no apparent reason that Anne couldn't have been pregnant with Stonor's child before she went to visit her guardian, the actual letter by Anne hardly implies such debauchery. Here it is, from the Stonor Letters and Papers (thanks to the Internet Archive):
306. DAME ANNE STONOR TO
SIR WILLIAM STONOR
27 FEBRUARY 
Syr, I recomaund me unto you in my most h[ert]y wise, right joyfull to here of yowre helthe: liketh you to knowe, at the writyng of this bill I was in good helthe, thynkyng long sith I saw you, and if I had knowen that I shold hav ben this long tyme from you I wold have be moche lother then I was to have comyn into this ferre Countrey. But I trust it shall not be long or I shall see you here, and else I wold be sorye on good feith. Syr, I am moche byholdyng to my lady, for she maketh right
moche of me, and to all the company, officers and other. I have early trust uppon your comyng unto the tyme of thassise, and else I wold have send Herry Tye to you long or this tyme. I have deiyvered a bill to Herry Tye of suche gownes as I wold have for this Ester. And I beseche oure blessed lord preserve you. From the Castell of Taunton the xxvij day of Februarer.
Your new wyf Anne Stonor.
Nowhere does this quite sweet letter mention Dorset, though the reference to "my lady" probably refers to Dorset's wife, Cicely Bonville. Would Cicely be making "right moche" of a young lady who was carrying on an affair with her husband? Would a young lady who was being sexually exploited natter on happily about her Easter gowns?
But it gets worse. Next, we're told that "His [Dorset's] treatment of Clarence's son, young Warwick (before 1483) may have caused the boy to be mentally retarded."
There are two rather big problems with this statement. First, as Hazel Pierce, the biographer of Margaret, Countess of Salisbury, points out, the evidence that the Earl of Warwick (Margaret's younger brother, Edward, who was executed by Henry VII on probably trumped-up charges) was mentally retarded rests on a single statement by Edward Hall that Warwick had been imprisoned for so long "'out of al company of men, and sight of beates, in so much that he coulde not descerne a Goose from a Capon.'" (An online version of Hall renders this passage as, "And Earl Edward, who had been imprisoned since childhood, so far removed from the sight of man and beast that he could not easily tell a chicken from a goose, although he had deserved no punishment by his own wrongdoing and had been brought to this by another man’s fault.") Read reasonably, this statement does not imply that Warwick was mentally deficient, simply that long imprisonment had left him ignorant and naive. Pierce also notes that in a later petition to Henry VIII excusing her brother's alleged treasonous behavior, Margaret described her brother only as unworldly and inexperienced, though it would have been to her advantage to describe him as mentally deficient had he been so. Henry VII himself never described Warwick as being mentally retarded ("idiot" is presumably the word that would have been used at the time), and neither did Richard III, though doing so would have been to both men's advantage given the potential threat to the crown the boy presented to them.
Assuming for the sake of argument, however, that Warwick was indeed mentally retarded, how on earth can Hampton assume that Dorset was responsible? If Warwick was retarded from birth (in February 1475), Dorset can hardly be blamed; if Warwick was normal at birth and was later damaged by childhood neglect or abuse, Dorset is only one of several possible culprits who had charge of Warwick before Henry VII took him over in 1485. Dorset did not obtain the wardship of Warwick until September 1480, over two years after Warwick's father, the Duke of Clarence, was executed; in the interim, Warwick was a ward of Edward IV. After Richard III took the throne, Warwick was put in the care of Queen Anne, though he spent most of Richard III's reign at far-off Sheriff Hutton. There is not a shred of evidence, however, that any of these people or their servants neglected or mistreated the boy before his long imprisonment at the hands of Henry VII began--and that includes Dorset. Indeed, Dorset in particular had an excellent incentive to treat Warwick well: he had many daughters, and might well have planned to marry one of them to Warwick.
Having thoroughly slandered Dorset, Hampton fortunately passes over Elizabeth Woodville's tomb in silence, but a trip to Salisbury Cathedral gives rise to the comment that Bishop Lionel Woodville, by a concubine "had a son, Stephen Gardiner, who became Bishop of Winchester." Evidently, Lionel Woodville had access to one of the earliest sperm banks in history: Lionel died in 1484, whereas modern historians put Stephen Gardiner's date of birth as being in the late 1490's.