Super Gran isn't just a fictional character from a children's book. These days 21st century Super Grans are alive and kicking – and wielding their magical powers across the country.

Post-war baby-boomers are light years away from their predecessors and have become a tour de force of their own. Today’s grandparents are active and youthful. They were swingers in the 60s and know how to enjoy life. Socialising comes easy and they’re in tune with their children's kids. What’s more, it's not hard to spot them.

There are currently 14 million grandparents in the UK, and one in two people have grandchildren by the time they're 54.

Super gran Jackie Highe is a mother of two and has five grandchildren. She was spurred into writing her latest book, The Modern Grandparents’ Guide, by mutual friends who kept commenting on how different it is being a grandparent today.

Highe, 60, can remember sitting on her grandfather's knee. “He always wore a big waistcoat. My grandparents were lovely, and I loved them but they were almost Victorian. My father’s mother was very strict and we were a bit afraid of her cause you always had to be on your best behaviour. My mother's mother was lovely. But they didn't play with us. We went to visit them and they cuddled us, but they weren't fun.

“I’ve been married for 40 years and we're very active grandparents. We go scuba diving, horse back riding and have our grandchildren to stay. The other day we took them to an open air museum. I stripped the kids to the waist so they could go and build bricks and get dirty and they had a ball! My gran never took us out for the day.”

As a hands-on grandmother, Highe is used to dealing with all sorts of emotional and practical dilemmas facing modern grandparents.

“We know lots of people whose children are divorced or may be living on the other side of the world,” she says.

The role of carer is a challenge in itself. Baby-sitting, overseeing homework, teenage sleepovers – knowing when to hold your tongue and when to speak up. Highe is the first to admit it’s not always easy.

“Half of you wants to be their parent in the sense that it feels very natural. And you’ve got them on your own without their parents around or anyone noticing. But you have to remember that you’re not. And it can be hard sometimes but if you’re not careful you can end up thinking, ‘Well I wouldn’t do it that way’ and then you start interfering and that’s a big no no!

“My experience is that even the most perfect grandparent will interfere at some point. There’ll be a time when you’ll say something and think, ‘I shouldn’t have said that, I should have kept my mouth shut’.

“The rule of thumb is to think about what’s really important in the long term and decide what you’re going to make your stand over. Say something like favouritism, it's probably worth putting your sixpence in and upsetting your children.”

Sometimes however, Highe says it’s best to keep your counsel.

“If it’s something like bedtime or table manners, don’t get involved. You should be able to judge from having your own children what things will really last. OK, you could argue table manners but I think it’s worth choosing your fights. Otherwise, you’re just going to be an interfering old bat!”

Highe talked to loads of grandparents and parents while she was researching the book.

With Britain having the highest divorce rate in Europe and the cost of living soaring, ‘free’ childcare was a hot topic. One group of grandparents have even set up their own support website, www.grannynet.co.uk, to advise their peers on negotiating looking after their grandchild.

Grandparenting may have its difficulties but Highe says it also offers incredible opportunities.

“As a grandparent you are in a unique position from a discipline and character-building point of view,” she says.

“Grandparents are special because when you’re with them they’re devoting their time to you. They haven’t got other stuff to do like housework. You’ve got magic powers in a way.”

How to be a good granny and grandpa
  • Love them, just love them.
  • See as much of them as you can – take them off your children’s hands when they want a weekend away.
  • Be relaxed with them and have fun – let your hair down and be a child with them. That way it’ll feel like being young again.
  • Don’t spoil them and don’t let them get away with murder.
  • Don’t have different discipline standards from their parents. You have to agree a strategy – smacking or not smacking – whatever it is, stick to it because otherwise you confuse your grandchild.
  • If you live far away, send them little parcels. Kids love getting things in the post. Email them or phone them. Don’t let things drift.

Especially for grandpa...

  • Babies aren’t just grandmothers’ business.
  • Have some confidence and get in there right from the start.
  • Try to be bonded and imprinted on that child by the time it’s 12 months old.
  • Don’t assume that some stuff is for them and some stuff is for grandfathers – it’s not, everything’s for both of you.