The younger generation of royals are known for being hands-on parents.
Prince William takes his dad duties very seriously, even coming up with new and improved ways of getting the kids to behave.
When he struggled to get Prince George to sleep, Wills devises a rather crafty method.
The secret? Running water.
William, Kate and Harry appeared before an audience to launch the royal family's mental health charity, Heads Together, where they also answered questions about the kids.
William revealed both kids have been difficult when it comes to bed time, so he runs the tap to soothe them.
During the same presentation, the three royals were asked to write down on a piece of paper what made them happy, US Weekly reports.
The Duchess of Cambridge wrote "a walk", while Prince Harry said "making people smile", and Prince William wrote "my children".
Aaw, you guys!