'It still hurts to hear his voice'
Nancy Sinatra visibly lights up at memories of recording the million-selling number one hit Somethin' Stupid with her father.
"Talk about an inspiring night," she says.
It took place one evening in 1967 at Capitol Studios in Los Angeles, where Frank Sinatra was recording bossa nova sessions with Brazilian guitarist and composer Antonio Carlos Jobim.
"It was breathtaking, such a privilege to be in that room and listen to these wonderful charts being played."
Nancy laughs with delight, recalling the arrival of the legendary LA session ensemble The Wrecking Crew who played on so many classic Sixties' rock and pop records.
Microphones were set up face to face, and father and daughter ran through their light, playful version of Carson Parks's flirty love song, with Frank goofing around, putting on a Daffy Duck voice and cracking jokes.
"We had a really fun time but when it came to doing a take, I was struggling because of his silliness. I thought, 'Oh Daddy, please don't do that on the record'.
"I had to come back afterwards, when he was gone, and they put my harmony on a different track. It's such a lovely song. My harmony is kind of monotonous, though. Daddy got all the good parts."
Frank Sinatra is such a giant figure in 20th-century popular music, it is easy to overlook that the young Nancy was an iconic pop star in her own right, a slender, miniskirted, deadpan blonde who starred in films with Elvis Presley and Peter Fonda and scored a succession of striking hit singles, from the go-go classic These Boots Are Made for Walkin' to the hazily psychedelic duet with Lee Hazlewood Some Velvet Morning and the sultry Bond theme You Only Live Twice.
She represented a particular ideal of pre-hippy Sixties' female sexuality, innocent but knowing.
That was all "back in the dark ages", as the lady herself jokes.
At 74, she has the stretched and startled, luxuriously styled, over-made-up look of LA showbiz royalty only reluctantly relinquishing her gamine beauty. But there is also a real sweetness and warmth to her, underscored by a shadow of sadness, qualities that suggest emotions are close to the surface.
She laughs easily, but becomes moist-eyed just as quickly, displaying a kind of openness that was always part of her appeal. The years don't seem to have toughened her up.
"It's not easy," she says, of talking about her father. "Most people, when they lose their dads, they go through a period of mourning and time begins to heal their sadness.
"But we don't have the opportunity to heal. I know my brother and sister feel the same. The man was probably one of the most photographed people who ever lived. You hear his music everywhere, without warning. It's like constantly being bombarded, like somebody putting their fingers in the wound. No, it's not easy."
The Sinatra name will always belong first and foremost to her father. Now Nancy is promoting a Sinatra centennial - it is 100 years since his birth on December 12, 1915.
There is a superb career-spanning CD, Ultimate Sinatra, out on Capitol/Universal. In July, the multimedia concert Sinatra: The Man & His Music returns to the London Palladium.
Nancy was born in 1940, the elder sister of Frank Jr (71, an arranger, singer and conductor) and Tina (66, a film and television producer). She was always aware that her father was a famous singer.
"My mother said I used to cry when I heard his voice on the radio, because he wasn't there, he was coming from this box, you know."
All the children hail from Sinatra's first marriage (of four) in 1939 to his youthful sweetheart, Nancy Barbossa. The couple divorced in 1951, when Nancy Jr was 11.
"My mom is the rock, she is the glue," she says of her surviving 97-year-old parent. "My dad was always there, even though he wasn't living in our house. He was always on the phone, always just a car ride away. Whenever he had a new recording, we would be the first to get the acetate. It would say, 'Play it loud', in Dad's handwriting."
She talks with pride and considerable expertise about his work but her voice softens when she touches on more personal memories. "He was just Dad, he was just there... naps on the couch when he would be exhausted. I used to say, 'Mom, why does Daddy come over here and want to sleep?' She said, 'Because he's relaxed here, it's a good thing, you should be happy'."
All the Sinatra kids took classical piano lessons. Nancy wanted to continue studying music at the University of California but "foolishly" dropped out at 20 to marry singer Tommy Sands (they divorced five years later). She embarked on a pop and acting career but didn't have any chart success until she hooked up with maverick country singer-songwriter Lee Hazlewood in 1966.
It is, nevertheless, an evident irritant to her that she has never really been appreciated as a musician.
"People don't credit me, they just credit Barton. I used to write three- and four-part harmonies for my YWCA club in high school. We used to win all the song contests. But people would say, 'Look who her father is, he probably did the whole thing.' My classic line was, 'Please remember, Nancy Sinatra will never be the man her father is'." She laughs. "That used to shut them up."
Nancy married again in 1970, to dancer-choreographer Hugh Lambert. He died of cancer in 1985, by which time she had dropped out of making music to raise their daughters, Angela and Amanda. She made a comeback 10 years later, and now tours regularly, releasing occasional albums. She posed naked for Playboy in 1995, aged 54, in what she has admitted was "a cheap publicity stunt" to drum up attention for her return. She has been dismissive of the notion that her father might not have approved.
"He had no right to scold anybody for impropriety!" It is a rare hint of approbation for her father's lifestyle. Of the many other women in Frank's life, she only bonded with his third wife, Mia Farrow (married to Sinatra from 1966-68), with whom Nancy remains "very close, she's a pal, I love her dearly".
She snorts with gentle laughter at the notion (floated by Mia in a 2013 Vanity Fair interview) that Farrow's son with Woody Allen, Ronan Farrow (27) may actually have been fathered by Frank.
"Oh, Mia's little joke? She was making a funny and it took off via social media. I mean, do the math, it's pretty ridiculous. But she's got a very funny sense of humour."
She couldn't listen to her father's music for 10 years after he died, and still finds it a bittersweet experience.
"It hurts, you know. It's a blessing really, that we can still hear that voice. If I had any advice to give to anybody, it would be record your parents talking, so that when you're longing to hear that voice you can play the tape.
"But for me, it's a little often. You don't always need to be reminded that he isn't here anymore."
Sinatra: The Man & His Music opens in July