Sarah Joyce -- aka the soon to be ubiquitous soul-jazz singer Rumer -- seems almost relieved when our conversation touches on what she half-jokingly refers to as "the scandal". "Do you know, most British journalists are too embarrassed to mention to it," she says, with a good-natured laugh. "A lot of them are a bit, 'oooh, I don't want to go there'. It's all rather awkward for them . . ."
Every family has a skeleton or two in the closet. In the case of Rumer's, though, it's more like half a cemetery's worth. Aged 11, she discovered the man she believed to be her father was, in fact, a cuckold -- her real father was a Pakistani chef with whom her mother had conducted a fling while the family was living near Islamabad (her "English dad" was an engineer on the huge Tarbela Dam project). To say the news came as a bombshell would be something of an understatement.
"You get information like that and your safety net vanishes," she says. "You are not secure. You go into an emotional space where . . .well, you kind of step out of your childhood early really. You create your own world where you can feel safe. It makes you feel like an outsider and that forces you to be creative in how you relate to other people."
In a round-about way Rumer is trying to explain how the family turmoil as a result of the affair -- her parents divorced not long after returning from Pakistan -- has shaped her as a musician. It certainly hasn't turned her into a snarling banshee. Someone who takes Karen Carpenter and Norah Jones comparisons as a compliment, Rumer harks back to the classic songwriter-pop of 70s Laurel Canyon. At her record company, they reckon they've unearthed a 21st-century Laura Nyro or Carole King -- though you suspect they'd settle for discovering the new Dido.
"It's weird. My album went to number two on the Amazon bestseller charts and it hasn't even come out yet. The guys from Amazon actually called the record label to ask what was going on. I'm actually really excited to meet journalists. They are the only people who have heard the record who are not friends, relatives or on the Warner payroll. I'm excited to know what you think of it."
Alongside the usual lashings of industry 'buzz', she has already netted a grab-bag of celebrity fans. Elton John has asked Rumer to duet with him at the Electric Proms in London next month. Over the summer, Burt Bacharach invited her to California. Weirdest of all, puggish British politician John Prescott recently gushed about her in a blog post for a London newspaper (think Willie O'Dea declaring himself a massive Vampire Weekend aficionado).
"He tweeted about it and, quick as a flash, the music editor at The Guardian said, 'go on, do us a piece for the blog Prezza'. He said, 'okay I'll give it a go'. He must have done it that night because the next day he had written a beautiful piece of journalism. It was very interesting, very surprising."
It was meeting Bacharach that most deeply affected her, however. Someone whose melancholy side glimmers through even on a sunny summer morning in a hotel in Dublin's Docklands, Rumer recalls being on the edge of tears as she and the veteran hit maker bashed out some songs at his piano.
"Do you know what was incredible? I'm standing there in his house, singing and he's on the piano and in front of me are all these photographs of his family. Out of the corner of my eye I see a beautiful picture of his daughter. She died tragically. She had autism and lived in a facility for young adults with disabilities. She had a lot of problems and she killed herself. And there I am looking at her picture and singing. I remember thinking, 'oh God, this is intense'."
Plain-talking and a bit on the mumsy side, Rumer seems almost too normal to be a pop star. At 31, she is far from an overnight sensation. A decade ago, she had a brief flirtation with fame when the band she fronted, La Honda, had a song featured in a Tic Tac commercial. She quit the group just as they were on the cusp of a breakthrough to nurse her terminally ill mother. At the time, walking away from La Honda was a terrible wrench. Looking back, she believes it was absolutely the right thing to do.
"I left for a few reasons. One being that my mother was ill. She said, 'oh please, don't leave the country'. We were doing well. We were at a crossroads. I could have gone one way with the band and been successful. But, you know, my mum was seriously unwell. Also, I didn't think I could be creative in that band. Malcolm was the songwriter. I sang his songs. Look at someone like Nina Persson in The Cardigans. Once you've been in a band, it can be hard to establish yourself as a solo artist."
Still, there were moments after her mother had died when she wondered if, by trying to do the right thing, she had inadvertently thrown her own life away. "It was a cul-de-sac. I woke up one morning and thought, 'where am I?' I was in a small town. My mum wasn't there any more. I had no reason to be there. I had nothing. It was so much harder to get back to London. What I did made it tough for me afterwards.
"On the other hand, I don't regret the experience of getting to know my mum before she died. You can't take that away."
Back in London, she joined the ranks of struggling singer-songwriters desperate for a break. Hers came out of the blue, at an open mic evening at which television composer Steve Brown -- doomed to go down in history as Alan Partridge band leader Glen Ponder -- happened to be in attendance.
"Mesmerised" by her husky, soulful voice and classic songwriting, he sought her out backstage and offered to finance her album. When her manager protested that Brown, with his light entertainment background, was too naff, she got rid of him. Her career has been on an upward trajectory every since.
With Joyce for a surname, it's no surprise that Rumer has Irish roots. Her maternal grandmother was from a well-to-do Rathgar family (her great grandfather was knighted as a Papal Nuncio by the Pope for his writings in church journal The Tablet). Moving to London, she brought her strict brand of Catholicism with her. This didn't affect Rumer too much -- but it impacted deeply on the life of her mother.
"It was definitely a negative for my mum. She got 100 per cent in her 11 plus exam and got a scholarship to St Paul's Girl's School. It's a top school. THE school really. People who go there, go on and become very important people in the world. My grandmother wouldn't let her go because it wasn't a Catholic school. She was also asked to model for French Vogue. My grandmother said 'no'. On the other hand, my sister got pregnant when she was 18. And everyone was okay with that . . ."
An unlikely cocktail of sex, death, betrayal and career upheaval, Rumer's early life story would have made for a wrenching true-life memoir. But, unassuming and chatty, she appears entirely unfazed. There is certainly no residual bitterness. She has a good relationship with her half siblings in Pakistan, supporting two of her brothers and their families with monthly donations.
"Where I go in the north-west frontier, it's beautiful, it's stunning, tall pine forests and valleys. Old men staring at the edge of valleys in contemplation whilst monkeys play nearby. There are fantastic people there. It's just the poverty. I don't think we would have so many problems with extremism, if the children were educated. I do it on a very small familial level. I'd love to be able to do it in a bigger way."
Isn't she being a tad rose-tinted? Surely there's a dangerous side to Pakistan, too?
"Oh yes. My mum said that, once, on a camping exhibition in Kashmir with a friend, they got stopped by militia. They were asked, 'what political party do you support?' Quick as a flash, mum answered 'yours -- now here's some money'. Hah! That's the Irish sense of humour for you."
Album Seasons Of My Soul is out next Friday