Speaking during an engagement on Monday morning, William revealed that George, who is now two, 'never slept' as a baby, and while his sister Charlotte, one, isn't 'much of a crier', George was when he was younger.
However, the father-of-two had a trick up his sleep to soothe the duo - turning on a tap, as the sound of the running water seemed to calm the pair.
William revealed that George 'never slept' as a baby
William shared his parenting secret at the launch of the Heads Together charity campaign at the Queen Elizabeth Olympic Park in London.
The project, which is championed by himself, wife Kate and brother Harry, brings together some of the country's most prominent mental health charities, including Mind, Place2Be and CALM, with the aim of ending the stigma surrounding mental health.
Both William and Kate were said to be particularly interested in an app called Baby Buddy, made by the charity Best Beginnings, which offers parents advice and support they might otherwise not seek help for.
William even commented that he wished he'd had it when he first became a parent, and said he'd like to see more done for fathers.
Talking to model Abbey Clancey, who was also in attendance at the event, Kate acknowledged that many people found it hard to ask for support with mental health issues.
'The trouble is many people put a sticking plaster over things and feel like they can't seek help for issues such as post natal depression, or may not even know they have it,' she said.
The Duke and Duchess appeared at Queen Elizabeth Olympic Park to launch their campaign
As they toured the various charity stands, the couple were given cards and asked to write 'what makes them happy'. Kate said that going for a walk lifted her spirits, while William simply wrote 'my children'.