Sis Heyster

In January 1944, Anne wrote that she had read an article by Sis Heyster about blushing.^[1] She pasted this article at the back of her diary and hung the accompanying photo of Joyce van der Veen on her wall.^[2] Sis Heyster (1909-1982) passed her master's degree in philosophy in 1935, majoring in psychology.^[3]  She became known for her many lectures and articles in magazines such as Libelle and Margriet, on parenting and developmental psychology. She attained her doctorate in 1942 with a dissertation on right and left-handedness and intellectual ability (Utrecht 1942).

Otto Frank sent her a copy of The Secret Annex in 1947, for which she wrote a thank-you note.^[4] The article to which Anne referred appeared under the title 'Een lastig verschijnsel' (A Troublesome Phenomenon) in the Libelle of 3 October 1941.^[5] She was the author of several books, including:

• Tweemaal ja. Gesprekken met verloofden ('Twice yes. Conversations with Fiancé(e)s' - around 1950).
• Rondom de telepathie ('On Telepathy' - Amsterdam 1939).
• Opvoeden in de praktijk ('Parenting in Practice' - Heemstede 1949).
• Levende opvoedkunde ('Living Pedagogy' - 1949).
• Het meisje ('The Girl' - Haarlem 1955).

Source personal data.^[6] Addresses: Leidseweg 65 bis, Utrecht (November ’36). She lived here with her older sister Geertruida Johanna, who was a teacher.^[6] Raphaelplein 8, Amsterdam (’47).^[7]