After his studies at the Institut Saint-Luc in Brussels, Sidney (pseudonym of Paul Ramboux) joined the magazine Tintin, where he made his first comics. He also worked for Spirou under pseudonyms like Kovak or Malois. There, he illustrated about 60 'Belles Histoires de l'Oncle Paul', as well as a long biography of 'Marco Polo'. After that, he made several short stories with writer Jacques Acar about the American Civil War, for Record magazine. In 1982 he returned to Tintin with his series 'Julie, Claire, Cécile', which he made with scenario writer Bom.