Margje & Sjoerd Kuyper. Sjoerd Kuyper has written over forty children’s books and won numerous major awards for his work, including the Theo Thijssen Award and Gouden and Zilveren Griffels (Best Children’s Book of the Year award). In addition to his work as an author of children’s books, Sjoerd Kuyper is a successful writer of film scripts, musicals, TV series and books for adults. His book The Knife was made into a film and tv series. The film received an Emmy Award. For this unique project he collaborated with his wife, the Dutch painter Margje Kuyper.