Earlier in the day, William and Kate spoke to schoolchildren on a visit to BBC's Bridge House in Media City, Salford. "It was amusing", he said according to The Telegraph. But at London's Thomas' Battersea this year, it was an opportunity to catch the budding four-year-old thespian in action as a sheep.
The 35-year-old William delivered George's Christmas list to Santa Clause last week when the couple was on a Helsinki, Finland tour, in which he mentioned a police vehicle.
Last month, William gave a speech at the launch of the taskforce at Google's London headquarters and said he hoped the United Kingdom could become a world leader on tackling cyberbullying.
In a question and answer session with the children, Josh explained he had told his father about his mental health problems.
He added: 'Mental health used to be this scary word that people didn't like talking about and it's slowly getting better now'. It was amusing, ' the soon to be dad-of-three told school children.
Serena Williams Entered Into Australian Open
I think one of the hardest days of all of our lives was having to tell our sister's children what happened to their mom. Tiley declared that Williams's return to tennis in Melbourne was "very likely".
When the Duke of Cambridge was in Manchester, he also met with his cyberbullying task force member.
He added: "Parents are feeling the pressure. We need guidance and support to help us through some serious challenges".
Kate will join a forum hosted by Sesame Street's Workshop, the charitable foundation of the children's TV show, on research commissioned into kindness.