According to The Third Millennium Online, English explorer Henry Hudson had three brothers: Christopher, Thomas and John. Like Henry, Christopher worked for the Muscovy Company, which dealt with trading between England and Russia. John Hudson was involved with English navigator John Davis' work trying to find the Northwest Passage.
Like Hudson himself, Henry Hudson's brothers were involved with the English shipping trade of the 17th century. However, Henry was working for the Dutch East India Company in 1609 when he attempted to find a more direct trading route between Europe and Asia, and ended up sailing the North American river which is now named after him.