But then Janet Ellis is no ordinary granny – and to be fair, her grandchildren Sonny, seven, and Kit, two and a half, aren't that run of the mill either, being the offspring of pop starlet Sophie Ellis Bextor.
But Janet takes her role as granny very seriously – so much so, she has been championing other grandparents in her role as a judge in the forthcoming Grandparent of the Year awards.
What sort of granny are you, traditional or thoroughly modern?
I like to think I'm both! I lost both my grandmothers before I was born, and my parents had lost their mothers in their teens, so I grew up grandmother free. But they both had grandmothers they adored, so I suppose I've got an idea about how they felt about them, which was very loving, very cosy and slightly naughty, so I think I wanted a bit of that!
Were you desperate for grandchildren?
Well, my other children were young when when Sonny was born – Martha was only 12 – so it was more like having a baby in the family again, rather than 'I wish she'd get on with it and have some grandchildren for me'.
You seem very close to Sonny and Kit?
Well, I suppose I'm not a special event, because we live very close to Sophie and I see the boys a lot, and the older boy goes to the same primary school that my younger two went to, so there's a lovely continuity, so I'm not a sort of 'Grandma's coming this weekend, everything else must stop' - I am sort of in and out of their lives.
Very hands on then?
I certainly do as much as I can, and yes, I really love it. And that's anything from picking one of them up from school, or going to sit with one of them while the other's going off and doing something, so they don't always have to be lumped in together, which I think is lovely for kids.
Do you think grandparenting has really evolved over the last few generations?
In some ways I think it has, and I think it helps everyone if they're a little bit flexible about it, instead of having expectations. But yes, I suppose because we're living longer and we're healthier, hopefully for longer, there are quite a lot of grandparents who are still working, and I know - I hear it from Sophie's friends - there are quite a lot of grandparents who simply aren't available, because they're off either working or having fun. To that extent it probably has changed, yes.
But I think what hasn't is the way you feel about your own children once they become parents, which I think is an extraordinary thing. And also for them, that they get to understand a little of what you went through, which is no bad thing, and it just broadens out the family connections in a really lovely way.
Both of Sophie's babies were born early – is it hard as a mum seeing your daughter go through that?
Well coincidentally, her sister, Martha, my youngest was born 10 weeks early, so both of us had the experience of special care units, although of course it's very different when it's your own child. But yes, absolutely, I'm really glad that I was there to support Soph through that, because there's no doubt that it was really sad that it happened the first time 'because it's horrible not to be able to take your baby home, and really jolly bad luck that it happened again - a million to one chance that she got pre-eclampsia twice, because that's absolutely not a given.
So yes, it was a sad thing, but then she's a very positive person too and the lucky thing is that both boys - although they were much too small to be in the world - were healthy, so they didn't have to have horrible invasive operations.
Do you think children rely on their parents for childcare a lot more these days?
Absolutely. Apart from anything else I take great comfort from that, because we're continually being told that the family is a fractured unit, that people aren't as close to their families as they use to be, and we don't live close. But actually, when you hear about that, there are an awful lot of grandparents falling into that category of helping financially or with time.
Are you ever an interfering granny?!
Without becoming too twee about it, I'm amazed at what a good parent Sophie is. She's incredibly busy, she travels a lot for work but you'd never know it when she's with the boys, she drops everything for them and - obviously they're used to it - but equally I don't think they feel a great gap because her energy is amazing and she's a loving and fun mother.
Do Kit and Sonny know all about your Blue Peter days?
Well, of course Kit's only two and a half, so he's yet to be underwhelmed by what I used to do. Somebody else was telling Sonny about me parachuting and I could see him just looking across and thinking 'This woman? No way'. So yes, at some point I will show him the film. I'm sure he doesn't believe it at all.
What's your absolute favourite part of being a grandparent?
You've got a chance to be a child again a bit, with all that means, just going for a walk and stopping and looking at absolutely everything and talking about absolutely everything. And of course, both my grandchildren - well, Sonny's edging out of this - are both young enough to think I know stuff and not mind when I dance, that's also a huge pleasure. It's seeing the world again and having that feeling of seeing little ones in the house where my own children were small is a huge pleasure.
Does it keep you young?
I hope so. Sonny's very tolerant that I wont let him on the highest thing on the climbing frame - I've said 'There are certain things I can do, but there are certain things I can't', and rescuing him from the top rung of the climbing frame is definitely one of them.
However, from a very early age he understood that at a certain point in the morning everything had to stop for Grandma's coffee. So I've instilled that one, that's been a successful learning curve.
Do you think it's important that we celebrate grandparents with awards such as Grandparent of the Year?
Of course! I think there should be awards pretty much every week of the year for grandparents.
The nice thing about this one is that there are lots of different categories, and although I'm sure, everybody thinks their mother is brilliant at all of them, it's really rather nice to have single things that you can sayyou admire and like and love about someone. It's been really good fun judging them and seeing why people think someone qualifies for either 'active' or 'glam' or 'fun' or 'amazing'. There are some good people out there and it's lovely that they're being recognised. I've worked with RIAS before and obviously they know I'm a grandmother because I never shut up about it, so I think they feel it was a good idea to ask me to judge some other ones instead of just boasting about my own!
What would your top tip be for a new grandparent or grandparent-to-be?
Probably that you don't have to do anything special. If you don't feel that you want to be on your hands and knees making animal noises on the floor, then don't. You have other skills that you can bring - often it'll be time, sometimes it's the way you see the world, sometimes it's that you'll sit and watch the same television programmes together. I don't think you should ever feel you need to put a different face on and a different feeling in your heart, because the person that you are is the grandparent they want you to be!