Fyraåringarnas hemliga liv säsong 4

As a new intake of fascinating five-year-olds arrive for work and play, the programme explores the difference between boys and girls, seeing how they interact with each other, and how their sense of gender roles is ingrained at such a young age.

Five of the girls and five of the boys return to the play centre, but how do they react when they find out that they have to share it with the opposite sex?