The portrait is Jacoba van der Vegt (1897-1970), a daughter of Jeanette van Konijnenburg-Van der Vegt, Willem's eldest sister. Jacoba was Van Konijnenburg's favorite niece. According to an eyewitness, there was 'true love' between her and Willem. Van Konijnenburg often joked that he and Jacoba had a relationship. The special bond between uncle and niece has been turned a blind eye by the family, including Netty van Konijnenburg-Kempers, the wife of Willem van Konijnenburg. Jacoba literally stayed with him until Willem's death, because she sat at his deathbed with his wife and another niece.
Many small and large drawings of her are known. Jacoba was also a model for important works such as 'Overgave' (Art Museum The Hague) and 'De unveiling' (Drents Museum Assen).
In addition to being a model/muse, Jacoba was also Willem's dance partner in the Tango. Jacoba worked as a teacher and has always remained single. After her death, part of Jacoba's Van Konijnenburg collection was exhibited in the Rosa Spierhuis in Laren (1971). There is work in private ownership and two paintings and a lithograph are included in the collection of Limburgs Museum Venlo.
According to the expert of the work of Willem van Konijnenburg, Bas van de Klundert.
