Being a member of one of the oldest continuing monarchies in the world must be a daunting prospect. The weight of expectation on your shoulders from the time you are born could be an overwhelming burden. The British royal family seems to take it in stride as much as they can, and all signs point to the fact that they try to be as normal and close of a family as possible. How they do this is a mystery to many, but there are clues like these old fashioned things the royals do that promote a tight knit family.
This isn't to say anything like "Royals! They're just like us!" because they most assuredly are not — I don't think many of us are in the position to receive gifts like a subversive hand spun lace from Mahatma Ghandi reading "victory for India" for our weddings as Queen Elizabeth and Prince Philip once did. Therefore, it takes real effort for the royal family to bring themselves close together and find some semblance of normalcy in their traditions. Over the centuries of their reign, they've become quite adept at carving out these moments together, even when prying eyes are looking in.