Prince William and Duchess Kate reflect on the challenging first few days with 'little George'

With the London Marathon fast approaching on Sunday, Prince William, Duchess Kate and Prince Harry sat down for a candid conversation at Kensington Palace on Friday to reflect on their work with Heads Together thus far. They began the campaign one year ago in order to "end stigma around mental health," and while they have since made strides, they know there's still work left to do.

During their outdoor chat, the group revealed that Heads Together was actually Kate's idea. As she puts it, "Because it's a common thread, wasn't it? Mental health seemed to run between all the different areas we were working in."

SEE ALSO: William and Kate will reportedly be bringing Prince George to school themselves

The three touched on everything from William and Kate adjusting to life as first-time parents to how William and Harry coped with their mother, Princess Diana's, death.

"Remember the first few days with little George? You know you have no idea what you're really doing. No matter how many books your read, nothing can prepare you for it," the duchess reflected. She even reminded William of how quickly they jumped back into their everyday routine only to realize how much of a "steep learning curve" parenting would actually be.

Three peas in a pod! See William, Kate and Harry's moments together:

The conversation quickly turned to the topic of William and Harry's grieving process, with Harry admitting that though he is now encouraging young kids to be open about their grief, he and his older brother never really talked about losing their mom:

"Both of us have always been open to each other, saying we've never really talked about it. We've never really talked about losing a mum at such a young age."

Kate sweetly went on to praise them both for their strength and resilience in the face of the trauma they endured.

Watch the full honest conversation below: