She revealed in an interview with Britain's Daily Mirror newspaper: "We
wanted to make it realistic and I watched it thinking, 'Oh my God, my dad's
going to see it!' And that was going through my head the whole time.

"But it was relevant to the story in that it's a movie about the 60s, and
sex and drugs and rock and roll were a big part of that.
"We didn't want to hold back because it is a real film and it is a gritty
film and there were a lot of shocking things and it wouldn't fit in the film
if we had an unrealistic sex scene."
Sienna's steamy scenes are with co-star Hayden Christensen, who portrays
rock star Billy Quinn.

In other news, Sienna Miller has apologized again to the people of Pittsburgh, Pennsylvania, after drunkenly calling their city "S**tsburgh" during an interview.
She says, "I said two controversial things after a bottle of wine. That monogamy is overrated and that Pittsburgh is 'S**tsburgh', which meant I was ostracized from the city. It was horrible, I got hate mail. English humor does not translate well at all. The monogamy thing was taken out of context because I believe in, and aspire to be in, a monogamous relationship."