And often splits in the family don’t help.
So for all the castles and horse-drawn carriages, the way Harry and Meghan have had to navigate family politics is what makes their big day just a little more relatable.
They are not unique in having divorced parents, and all the issues that throws up.
Meghan’s mother, Doria Ragland, and her father, Thomas Markle, have done their best to keep out of the press.
It has led to suggestions her dad wouldn’t be at the wedding, that they aren’t close, and he wouldn’t walk her down the aisle, but the couple have squashed those rumours by announcing that both Thomas and Doria will have important roles on the big day.
There is of course the often slightly awkward “meeting of the in laws” moment especially if divorced parents are involved.
I think most of us can sympathise with that; cue artificial small talk or general banter about what your daughter was like as a baby.
But this transatlantic relationship has meant that for Harry and Meghan that meeting has been delayed for longer than you’d normally expect, with the Markles and the Windsors only getting together for the first time in the week running up to the wedding.
Prince Harry hasn’t met his father in law in person yet, although they have spoken on the phone.
From every encounter I’ve ever had with the likes of Prince Charles, Prince William and Prince Harry they are remarkably down to earth, and I’m sure for Harry they’ll make every effort to welcome Meghan’s mum and dad.
But how on earth do you get your head around your daughter marrying into one of the most famous families in the world? Sitting down to tea with the Queen, Prince Philip and Prince Charles, knowing that in a few days’ time your daughter will marry into the British establishment?
The mud-slinging from Meghan’s half siblings must have been another difficult thing for her to deal with, and another sign that it isn’t all happy families.
An open letter from her half brother Thomas Junior suggesting Harry should walk away from the wedding was astonishing.
But again it’s been a reminder that actually this Royal romance has had its hurdles.
No doubt on 19 May both their families, well those who’ve been invited, will wish them well and like any wedding party muddle along to make it the best day possible.
The same as any family really, except for these two a worldwide audience of millions will also be watching.