Steffi & Michael Gerharz (aprilkind) live with their three children. The idea for the Grumbletroll came to them when their youngest daughter was sitting at the breakfast table with her arms folded, sulking and grumbling. 

Barbara van den Speulhof is a children’s book author and director and producer of radio plays for children.

After short periods in mechanical engineering and architecture, Stephan Pricken studied primary-school teaching with a focus on art, and then graphic design.

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