Do you have plans to kill Adrian Mole off?

The only way I’ll kill Adrian is when I die myself.

What’s your relationship with him like now?

I made the mistake in the early books of making him not very attractive. But I have recently fallen in love with him. He has got older. He has taken advice from women on clothes and hair. Tragic happenings make him attractive as well. He has come to learn you don’t need things. There is joy in seeing a tree come into blossom.

Do you feel the same yourself?

Adrian Mole, c’est moi.

The Prostrate Years includes startling comedy – a dead guide dog chapter…

It is the third dead dog Adrian has buried. He asks: why does everyone ask me to bury their dead dogs?

If you had not been registered blind, could you have written this way?

No, I wouldn’t have dared.

Have you got a guide dog?

No, but we have Bill, a black labrador.

You once likened yourself to a golden labrador?

Yes, I hate it when people call me a “national treasure”. It takes away your bite and makes you feel like a harmless old golden labrador.

Any other labrador attributes?

Yes – I am usually overweight. I have had to be interested in diet because of being diabetic for 30 years and having kidney failure. Did you know I had a transplant last year?

I read that your son donated his kidney – that must have been traumatic…

Not for me. But for him, I think – he was giving away a healthy organ. It was incredibly brave.

Did you have counselling beforehand?

No – a talk with a vicar. I am surrounded by counsellors. My sister is a counsellor. My daughter is training to be a counsellor. A lot of my friends are counsellors.

And could you be a counsellor?

I have been, unofficially, for years.

Was it useful talking to the vicar?

No. I had my husband and son in the room. That was a mistake. I might have wanted to talk about how scared I was about my son and couldn’t.

Were you frightened for yourself?

Once I found out I would be given a morphine drip I could control, no.

How is your new kidney doing?

It’s fine! You can see it [points to a pouch-like accessory to the stomach]. They didn’t put it in my back because the arteries aren’t that good. They put it here so I can feel it. It is really odd. It’s like feeling a baby. It’s doing well.

Congratulations! But you have been cursed with such outrageously bad health. How come, unlike Adrian, you seem not to be a hypochondriac?

I am the opposite. I ignore myself until it gets acute. I had TB peritonitis at 23.

And is the diabetes a tyranny?

A total tyranny – I have never managed it properly. I am the world’s worst diabetic.

Was the blindness diabetes-related?

Yes, the small capillaries in the body burst easily. I was working all night on the TV series The Cappuccino Years, putting a strain on my eyes. Eventually, the capillaries burst and blood flooded the backs of my eyes. I woke and thought the room was full of smoke but couldn’t smell anything. I was halfway upstairs before I realised it was in my eyes. One eye cleared quickly, the other didn’t. But it meant a huge amount of painful laser treatment to the back of the eye.

Such extremes of success and distress…

Sometimes I rant, in a comical way, about how the gods give with one hand and take with the other.

I was amazed to re-read Adrian Mole’s first words (a new year’s resolution): “I will help the blind across the road.”

Yes, I couldn’t believe it – so prescient. When I was a child, I dreaded blindness. We used to ask: would we rather be blind or deaf? I said I’d rather be blind, even though I was scared of it. I couldn’t bear not being able to hear music or talk to people.

Adrian worries about emotional detachment. Are you detached, too?

I have a certain detachment. If I gave in to my emotions, I would cry me a river.

What – who – makes you laugh?

Russell Brand makes me laugh because he is such an adorable person. His heart is as big as Manhattan. He is living there now.

What makes you angriest?

Corruption in government….

How does Adrian feel about the coalition?

Adrian was disenchanted with New Labour… And my God, the new government is getting things done quickly. I love that. Yet Vince Cable is already full of self-loathing. You look at him (I can see the television if I sit inches from it) and his head has gone skeletal, the joy has gone out of him and he is ashamed of himself, because the compromises are going to be too great. Nick Clegg has been publicly demoted. David Cameron's voice is getting more and more Bullingdon club. Adrian would be bewildered.

We love Adrian partly because he is a failure. How much have you failed? Did you fail school exams?

I failed everything – including cycling proficiency.

What was your worst failure?

I could have been a better mother. My children assure me it was fine. But when you are running to catch the train to go to a rehearsal and you know your kid has a hacking cough… We said we can have it all and do it all: I can have four children, write three plays a year and a book, go from Leicester to London and come back at midnight. But you can’t do it all.

Is it easier being a grandmother?

Yes, I have 10 grandchildren, nine granddaughters. It is like a fairytale isn’t it?

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