While George and Harry's relationship spans years, Amal and Meghan also share a long-standing friendship.
The Hollywood glamour pair flew Meghan and Harry via private jet to George's luxury residence on Lake Como after their May nuptials, where they received a crash course in parenting after meeting the pair's one-year-old twins, Ella and Alexander.
A source close to both famous couples told Daily Mail: "Amal and Meghan have been close for years, and Harry and George have become buddies because of that.
"They're much closer than the headlines let on."
The insider adds that George has "told a couple of people he has a strong hunch" that they'll be among the couples asked to form such an important role in their little one's life.
Prince Harry and Meghan will welcome their first child next year.