The head teacher said the royal helper had been "really chatty" with the children on the bus, playing I-spy with them and helping with their jumpers. The children were visiting a trail around the gallery encouraging them to think about their emotions, linked to Catherine's early years education project, Shaping Us.

The Princess of Wales was reportedly “animated” and “nurturing” with the little ones during Tuesday’s National Portrait Gallery outing.

The Princess of Wales took a school bus to the National Portrait Gallery with a group of young children and joined them on an interactive trail exploring their emotions through paintings. Kate adopted the role of a surrogate mum and held hands with some of the four and five-year-olds as she stepped off the minibus with the reception class pupils,