It is now the law to describe Meghan Markle as “revolutionary”, judging from the media coverage she inspires. Whether this is by parliamentary or palace decree, I’m not quite sure (I’m American so, like Markle, still not entirely up to speed with all these British rules). She is a woman of mixed heritage in the royal family, which is certainly revolutionary. Unlike previous women – her mother-in-law Diana, most obviously – who have been lumbered with tricky relatives on their side of the family, Markle shows a pleasing resistance to being the accommodating little lady and has, apparently, told hers to go jump.

Is that revolutionary? It’s certainly admirable. In the past week alone, I’ve read at least four articles claiming that Markle’s appearance in public with a non-flat postpartum stomach was revolutionary. Admittedly, her sister-in-law, Kate née Middleton, did exactly the same after her births, and Kate is widely agreed to be about as revolutionary as a wet tea towel. So perhaps in this particular case, Markle’s much-commented upon “mum tum” has less to do with her revolutionary spirit and more with female physiology.

There’s no question Markle is a trailblazing figure. But as Les Misérables taught me long ago, it’s not easy being a revolutionary. You don’t have a template to follow and, before you know it, you’re all alone in a tavern singing to the empty chairs at empty tables. But help is on hand in the form of… me. Admittedly, I don’t have an insight into being mixed race among the Windsors, but I do know something about being an American mother raising an English child. Markle is not the first person to do this. But she is the first in her family, and take it from the voice of wizened experience: it’s a transatlantic minefield. Allow me to describe some of said mines.

Mom v Mum

Every bone in your body screams that you’re the baby’s “mommy”, but everyone is saying you’re his “mummy”. The tweeness sets your American dentistry on edge, and “mummy” makes you think of ancient Egyptian corpses – and yet, you find yourself slowly yielding to the inevitable. After all, isn’t insisting on “Mom” in Britain a bit like those European parents who demand their poor kids call them “Maman” and “Papa” in public, even though they were born and raised in Manchester? So fine, you go with Mummy. And then, just as you’ve got used to it, you learn that kids in the Midlands call their mothers “Mom”. What can I say, Meghan? This country is confusing.

US citizenship

“There is no such thing as reproduction. When two people decide to have a baby they engage in an act of production,” writes Andrew Solomon in his brilliant book Far From The Tree, about parents having to accept that their children are not, actually, miniature versions of themselves. And while most parents understand this intellectually, it sure as hell won’t stop them trying to force a little bit of their own childhood down their kids’ throats. For some, this means recreating their memories (“Dad, why are we having a picnic in the rain?” “Because it’s fun”). For an American abroad, it means deciding whether to register your child as a US citizen. Anyone who grew up in America will have been indoctrinated into thinking that US citizenship is the most valuable asset a human can possess. So in those heady postpartum days, your instinct kicks in and you make your kid’s citizenship official. He might call you “Mummy” but he will be American, dammit. And just when you’re admiring your baby’s US passport, you realise what you’ve actually done: cursed him with filing US tax returns for the rest of his life. Shoot! I mean bugger!

The accent

It’s a little weird to hear your child talk differently from you. But it is not without its advantages. I like to make my children say certain words – “water”, “can’t” and, my favourite, “roly poly” – just so I can laugh at how adorably hilarious they sound. It’s good to do things your kids can discuss with their therapists in 30 years’ time.

British holidays

American family holidays are pleasurable sensory experiences: a trip to a sunny beach, say, or building snowmen at Christmas. You don’t have to go far to enjoy fun weather extremes. British family holidays, by contrast, are endurance tests, because the national climate is best described as “meh”, meaning holidays here are invariably grey and slightly too cold. But it’s also a reflection of the British attitude that comfort is for wimps. So in America, a beach holiday essential is sun cream; in Britain, it’s three stripy windbreakers. It’s unlikely Markle will be suffering too many wet holidays in a bungalow in Devon, but who could blame her if, while she and baby Archie shiver through another week at Balmoral, she thinks longingly of Disneyland?

Meghan, just wait until he can say “roly poly”. It’s almost as heartwarming as actual sunshine.

• This article was amended on 20 May 2019 to clarify that in many cases a child born abroad to a US parent becomes a US citizen by default, however they still need to be registered as such.