The Secret Life of 4, 5 and 6 Year Olds

A group of four-year-olds meet and forge new friendships. Surprise visitors arrive - 10 eggs in an incubator - and the children watch in excitement as they hatch during the week.

The four-year-olds are back but this time they're joined by some new faces. The week starts off with a bang as new girl Milana clashes with alpha girl Evie-Rae. Tensions continue to rise as the girls are teamed together for a building task.

Ten new five-year-olds make their debut at the play centre. After spending a year at school, these children assert their independence and are keen on exploring the adult world around them.

The five-year-olds meet some new children so that the experts can observe how they deal with competition.