The 26-year-old millionaire novelist, whose fourth book, A Place Called Home, is published tomorrow, said: "I'm conscious of the fact that when I see Dad that I don't want to talk about work and about politics. We go out every Sunday and we talk about other things in the world, normal things . . . how does he feel, what does he want to dof But it's great. If there's something that I don't understand, he's just the best person at explaining and he just breaks it down."

Ahern revealed that growing up in the public eye had forced her to develop a certain reticence. "I always used to tell people I had a very normal upbringing, everything was very normal . . . and it was very normal . . . but me and Georgina had this, I suppose, carefulness with people. It was very natural. Immediately we knew who to trust and who not to trust and who to have a certain conversation with and who not to, " she told the Sunday Tribune.

"We just learned from a young age. I remember from the age of four and five, picking up the phone and it would be a reporter, looking for Dad and we'd say 'No, you'll get him at the office'. Can you imagine a four- or five-year old just kind of knowing the right thing to say?"

The coinciding of her current publicity campaign and her father's recent political troubles could prove potentially distracting for the book, but she insists: "I don't mind people asking, I'm not afraid of answering anything but it's all blown over anyway.

Everything is fine."

Despite a number of newspapers stories about her in recent years that she described as "nasty", Ahern hasn't been subject to undue intrusive media attention of late. However, there have been some exceptions. "I go to Kerry with my Dad every year and for some reason they've started taking photos of us . . . they've done that the last few years. We always forget when we're down there, and then we're just walking down the street and I'm looking awful in a tracksuit or something, " she said.

In Ahern's view, you can play your part as a cog in the celebrity machine or you can opt out, which she said had been her decision. "You can live in that world or not live in that world, but I'm not interested, " she said. "But sometimes it's not a choice . . . when you're on holidays and they take your picture? They haven't said anything bad, it's just a photograph, but you wonder why they need to capture someone's life?"

Ahern, who wrote her first book, PS I Love You, at the age of 21, admits to reading some of her reviews this time around, something she opted not to do in the past. "At the beginning, I didn't, because they were so not reviews . . .

basically any review that mentions your mother, your father and your sister, then there's something wrong with it, " she said.

Her connections . . . sister Georgina is married to Westlife star Nicky Byrne . . . coupled with a $1m advance from US publishers, were guaranteed to attract attention, but the backlash to PS I Love You was particularly vitriolic.

Looking back, she said she's surprised by how unaffected she was by criticisms of what she calls a "genuine labour of love". "The reviews I did read I thought were humorous, because it was 'the Dad likes gravy, does Bertie like gravy?' It was so ridiculous."

All Ahern's books have been bestsellers and a film version of PS I Love You, starring Oscar-winner Hilary Swank, is currently being filmed in Wicklow. The film rights for Ahern's third novel, If You Could See Me Now, have also been optioned by Walt Disney for development as a musical starring Hugh Jackman.

But such successes haven't stemmed the sniping. Of a recent radio interview, she said: "The presenter read out a text to me from someone saying 'Cecelia only got her deal because she was Bertie Ahern's daughter and that's it', and she (the presenter) kind of looked at me and I thought, 'Oh, ok, thanks for bringing that up in a live interview, that's nice!' It doesn't get to me. I know there are five million people who've enjoyed it or that there are two movies being made. I just look at the positive."