Rik is Aart's nephew. Concerning Aart's role on Sesamstraat, it's often said that "Aart is the snake in the paradise named Sesamstraat." The early episodes of Sesamstraat had no grumpy character, which made the street scenes a little dull and preachy at times. One of the writers suggested a man named Buurman Bol (Neighbor Bol) who hated everything, but he never made it because he was too negative.