Katy Perry showed young girls exactly what they don't need to do - Christa Ackroyd

And then only if they dared to dream big.

My granddaughters range in age from 13 to two and what makes it all the more exciting for me, their crazy Nonna (their words not mine), is to see who they are already becoming in their own way, in their own time.

Because already they are all so wonderfully different. As they should be. We don’t want clones, we want individuals.

I suspect the two year old is going to be the well, shall we say, the wildest.

The seven year old who looks like an angel and displays all the signs of having the devil in her, the most stubbornly defiant.

The four year old is just the sweetest girly of girls, the nine year old the most serious and determined and the teenager, like all teenagers on the cusp of changing from girl to womanhood, the one with the most angst about fitting in, but will find her own path, as they all will.

And I will be there to guide them whenever they choose to ask (and sometimes when they don’t) offering support and lots of craziness along the way.

They are my greatest joy and being their grandparent my greatest challenge.

Which might seem a strange thing to say. But it’s a tough world out there and they will need all the help they can get.

Grandparents are quite rightly there to spoil their grandchildren, to say yes to things that responsible parents say no to, and that includes chocolate cereals for breakfast if that’s what they want.

Oh and television (supervised) in the bedroom way past their bedtime in school holidays. Moderation is for parenting. What goes on in Nonna’s house stays in Nonna’s house and is strictly between us.

But there is a serious side to grand-parenting, Nonna style. It is my absolute responsibility away from the stresses and strains of them growing up in well ordered well disciplined households to let them be who they want to be.

And more importantly let them know that can be anything they want, while still insisting that kindness wins, politeness rules and manners are everything. And it is a role I relish.

Which is why I will not be introducing them to Katy Perry’s self indulgent space adventure as a means of showing them anything is possible.

The one thing all my grandchildren will need to know is that success comes with hard work, determination and with putting others at the centre of your ambitions and not by donning a designer space suit while hitching a ride on others coat tails for publicity, especially if that ride costs billions of dollars for eleven minutes of floating free while others can’t even afford the fare to ride on a bus.

It is such a pity, such a wasted opportunity, all wrapped up in the false notion of female empowerment, that led one proper astronaut, one Nobel prize nominee and other assorted celebrities and girlfriends to take to the skies and beyond.

Because it was lacking one thing all successful women should wear, humility. And it isn’t about forging a path for the sisterhood if one of your besties is the girlfriend of the richest man on the planet who happens to want to promote his space travel business.

All that guff of jumbled rhetoric about doing it for love, being ‘super connected to life’ worse still ‘putting the ass in astronaut’ from Ms Perry was exactly what I will tell my girls they don’t need to do and that’s show off for showing off’s sake.

Which was all it was, a show of ‘it’s not what you know it’s who you know,’ a show of garbled incoherent ‘look at me singing wonderful world in space’ claptrap which ended up showing nothing but a complete disregard for the struggles going on for many women, and for men, down below on planet earth.

And certainly not a show of proving anything is possible.

A few years ago I put a video together for hundreds of aspiring young women at an event designed to get them interested in STEM subjects, science, technology engineering and maths.

In the auditorium we played Katy Perry’s Roar at full blast because we believed it to be the perfect soundtrack for young women wanting to make their mark in a traditionally man’s world.

The lyrics are about being knocked down and getting back up, having the fight of a tiger and roaring through life.

They were not about ‘look at me hitching a ride on my best mate’s boyfriend’s space ship and pretending it is one giant leap for womankind’.

Don’t get me wrong there is more to space than it’s vastness. And it isn’t all about going there because it is simply there to be explored.

My lovely and infinitely cleverer than me good friend Carol Vorderman is rightly proud of her daughter’s achievements in the field of space.

Katie King is an award winning technology superstar who happens to have been trained at NASA after graduating from Cambridge.

Her company is using space to build a pharmaceutical factory in orbit developing antibodies into tiny crystals which, if I understand it correctly, makes them smaller, purer and injectable rather than if they were made in earth, which in turn means hours of cancer chemotherapy treatment via a drip would be replaced with one single injection.

Yet Katie, a leader now in the world of Nanoscience, doesn’t shout about her own personal achievements just the importance of her work and her message that just like her every young girl out there, you can do and be what you strive for while discovering endless possibilities about the world, and about yourself with hard work, courage and determination.

And so to my granddaughters I would simply say this. Yes anything is possible. Yes you can fly. Yes you can reach for the stars. Yes the world is your universe.

But unlike Katy Perry just remember to always keep your feet on the ground. And scrap the need for a skin tight flying suit. You don’t need to impress anyone, apart from yourself.

You and only you are captain of your ship. And in the words of Glinda and Elphaba only you have it in you to keep defying gravity.

And you do that by staying humble and grounded, not by kissing the earth, or posing with a daisy in a skin tight designer outfit after eleven minutes of self promoting nonsense with Oprah and a handful of Kardashians watching on for good measure.