The number of happy faces on Lego toy mini-figures has been decreasing since the 1990s, and the number of angry faces has increased, giving rise to concerns that children could be affected by the negativity of the toys.

In a study of 3,655 figures produced between 1975 and 2010, Dr Christoph Bartneck, a robot expert at the University of Canterbury in New Zealand, said the manufacturer appeared to be moving towards more conflict-based themes in its toys. Bartneck’s study considered the range of facial expressions across various Lego sets – now often in themes such as Star Wars, pirates or Harry Potter. (The Guardian).