In Double Portrait of Prince Willem III and his Aunt Maria as Children, we see two young figures, Prince Willem III and his Aunt Maria, depicted with soft, warm colors. The children are dressed in rich garments that signify their royal status, with intricate details in their clothing. The background is a muted, dark tone that enhances the brightness of their faces and attire.

Their expressions convey a sense of innocence and curiosity, typical of childhood. The painting is an oil on panel work, which was a common medium during the Dutch Golden Age. Gerard van Honthorst employs a chiaroscuro technique, creating a strong contrast between light and shadow that brings depth to the figures. The careful attention to detail in the children's clothing and facial features showcases the artist's skill in portraiture.

The dimensions of the painting are approximately 60 x 80 cm, making it a medium-sized work. Gerard van Honthorst was a prominent Dutch painter known for his portraits and genre scenes during the 17th century. This particular work, created in the 1650s, reflects the artist's ability to capture the essence of his subjects with warmth and realism. An interesting fact about this painting is that it highlights the close familial bond between Willem III and his aunt, which is significant in the context of their royal lineage.

Today, it is housed in the Mauritshuis, a museum renowned for its collection of Dutch Golden Age paintings.