There has been much conjecture about the identity or inspiration of Kitty, who in Anne's revised manuscript is the sole recipient of her letters. 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. Anne does not mention Kitty 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 unposted letters to a real friend are two farewell letters to Jacqueline van Maarsen, from September 1942.
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. However, Kitty Egyedi said in an interview that she was flattered by the assumption, but doubted the diary was addressed to her:
|“||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.||”|
|— Kitty Egyedi|