 Jan Bondeson ( 1992 and 2006 ) proposed that , while the names " Eliza and Mary Chulkhurst " are not recorded in any early documents and are likely to have been a later addition , the existence of the twins and the claimed 1100 year of birth cannot be dismissed . Although mediaeval chronicles are unreliable , he noted multiple reports in the Chronicon Scotorum , the Annals of the Four Masters and the Annals of Clonmacnoise of a pair of conjoined sisters born in or around 1100 , although all three are records of Irish history and none mention Kent as the location . He concluded that the case of Christine McCoy , who survived for eight hours following the death of her polypagus twin Millie , shows that the claimed six hours between the deaths of the Biddenden Maids is plausible , and agreed with Ballantyne 's proposal that the idea that the twins were joined at the shoulder is a later misinterpretation of the figures on the Biddenden cake . He also pointed out that although there is no recorded version of the legend prior to 1770 , there would have been no possible motive for the villagers of the 18th century to fabricate the story . 
