When I was seven ...

I started writing a diary. I think that has been the best training for my writing as I would do it every day – and continued to until I was 20. I would write how I was feeling, that this person said something or I fancied a boy. It was all very innocent.

The wisest thing my grandmother told me ...

It's not so much something she said as her general behaviour that was a real lesson to me. She was very religious and strict, but there was another side to her that was quirky bordering on eccentric. When we would go out with her she would take her false teeth and chatter them at people. Or she would break out into random song or start dancing in supermarkets. I loved that side of her. I call it the "crazy Kelly gene".

The biggest adversity I have overcome ...

My "quarter-life crisis" in my early twenties. I had left college and was trying to decide where on earth I was going. It was a confusing and sad time. I turned to writing and wrote PS, I Love You. That changed everything in my life.

My motto for life ...

Dream – then make it happen.

My soul mate is ...

Although I adore my husband and wouldn't ever want to be without him, I have to say my children because I feel connected to them in a different way – they are part of my soul. I have two: Robin, two, and Sonny, 11 weeks.

Not many people know that ...

I still suck my thumb and have a blanket. His name is Sniffy. I got him as a present when I was two – he is a pillowcase. In fact, I'm holding him right now. He is ratty tatty, torn, burned and has been through the horrors.

The most inspiring book I've read was ...

The Celestine Prophecy by James Redfield. I read it at a time when things were changing in my life. I'd just got the [publishing] deal for PS, I Love You and was feeling overwhelmed by everything. It was a book that made sense to me and opened up my mind to life.

What I look for in a friend is ...

Loyalty and a sense of fun. I'm not the kind of person who needs to speak to someone every day. Some of my friends and I will go weeks without hearing from each other, but then we pick up right where we left off.

The first people I ring when I'm upset are ...

My husband David or my mum. David is amazing at knowing the right thing to say. He is balanced and never gets dramatic. He understands me well and is good at putting things into perspective.

I believe the secret to a strong relationship is ...

I hate when people give relationship advice because everyone is different. What I try to do is let each other be who we are and not try to change each other.

Something I wish I'd done earlier ...

Got fit. It's only since I've had my daughter that I'm now the fittest I've ever been. Before that I spent my twenties working/travelling and not being active.

My all-time favourite YouTube clip ...

Jimmy Kimmel and The Handsome Men's Club. It's him and all these Hollywood men. He's the president and they are deciding who to let into the club – it's clever and funny.

My childhood hero was ...

Take That. I had posters of them covering my bedroom walls and ceiling. They helped me get through those difficult teenage years from 12 to 15.

My brother-in-law [Nicky Byrne] is in Westlife and they were on X Factor with Take That. I didn't want to meet them, though, as I knew I would be reduced to a besotted teenager. Sometimes it's best not to meet your heroes.

One Hundred Names by Cecelia Ahern is published by HarperCollins, priced £14.99