For many years there was much conjecture about the identity of or inspiration for Kitty. In 1996, the critic Sietse van der Hoek wrote that the name referred to Kitty Egyedi, a prewar friend of Anne's. Van der Hoek may have been informed by the publication A Tribute to Anne Frank (1970), prepared by the Anne Frank Foundation, which assumed a factual basis for the character in its preface by the then-chairman of the Foundation, Henri van Praag, and accentuated this with the inclusion of a group photograph that singles out Anne, Sanne Ledermann, Hanneli Goslar, and Kitty Egyedi. However, Anne does not mention Egyedi in any of her writings (in fact, the only other girl mentioned in her diary from the often reproduced photo, other than Goslar and Ledermann, is Mary Bos, whose drawings Anne dreamed about in 1944) and the only comparable example of Anne's writing un-posted letters to a real friend are two farewell letters to Jacqueline van Maarsen, from September 1942.[27]
Theodor Holman wrote in reply to Sietse van der Hoek that the diary entry for 28 September 1942 proved conclusively the character's fictional origin. Jacqueline van Maarsen agreed, but Otto Frank assumed his daughter had her real acquaintance in mind when she wrote to someone of the same name. Kitty Egyedi said in an interview that she was flattered by the possibility it was her, but stated:
Kitty became so idealized and started to lead her own life in the diary that it ceases to matter who is meant by 'Kitty'. The name ... is not meant to be me.[28]
Only when Anne Frank's diaries were transcribed in the 1980s did it emerge that 'Kitty' was not unique; she was one of a group of eight recipients to whom Anne addressed the first few months of her diary entries. In some of the notes, Anne references the other names, suggesting she imagined they all knew each other. With the exception of Kitty, none of the names were of people from Anne's real-life social circle. Three of the names may be imaginary, but five of them correspond to the names of a group of friends from the novels of Cissy van Marxveldt, which Anne was reading at the time. Significantly, the novels are epistolary and include a teenage girl called 'Kitty Francken'. By the end of 1942, Anne was writing solely to her. In 1943, when she started revising and expanding her diary entries, she standardised the form and consolidated all of the recipients to just Kitty.
