In Portrait of Catharina Pottey, Sister of Willem and Sara Pottey, Nicolaes Maes presents a young woman in a richly detailed dress. The colors are warm, with deep reds and golds that highlight her attire. Catharina's expression is serene yet engaging, inviting viewers to ponder her story.

The background is subtly painted, focusing attention on her figure. The painting is executed in oil on canvas, a common medium during the Dutch Golden Age. Maes skillfully uses light and shadow to create depth, particularly in the folds of Catharina's dress. The details in her clothing and the textures of her skin are rendered with precision, showcasing Maes's technical abilities.

The composition is balanced, with Catharina positioned centrally against a muted background. Nicolaes Maes was a prominent Dutch painter known for his portraits and genre scenes. This work, created around c. 1665, reflects the artist's transition from genre painting to portraiture.

Interestingly, Catharina Pottey was part of a well-known family in the Netherlands, and her portrait serves as a testament to the importance of familial connections in 17th-century Dutch society. Maes's ability to capture character and individuality makes this painting a notable example of his work.