Bonham Carter takes over the role of Queen Elizabeth's sister Margaret from actress Vanessa Kirby. Margaret died in 2002.
"She (Margaret) said, apparently, she was glad it was me. My main thing when you play someone who is real, you kind of want their blessing because you have a responsibility," Bonham Carter claimed at the Cheltenham Literature Festival, reports theguardian.com.
"So I asked her, 'are you OK with me playing you?' and she said, 'you're better than the other actresses they were thinking of'. They will not admit who it was. It was me and somebody else. That made me think maybe she is here, because that is a classic Margaret thing to say. She was really good at complimenting you and putting you down at the same time," said Bionham Carter.
"Then she said, 'but you're going to have to brush up and be more groomed and neater'. Then she said, 'get the smoking right. I smoked in a very particular way. Remember that this is a big note the cigarette holder was as much a weapon for expression as it was for smoking'," the actress added.
Bonham Carter also said that taking over the role in seasons three and four of "The Crown" from the Bafta-winning Kirby is "definitely daunting".
to prepare for the role, she went to Margaret's inner circle.
"Three ladies-in-waiting, a couple of relatives, a very close relative and some really close friends. They loved the woman and were very happy to talk about her because they miss her," the actress said.
Bonham Carter feels Margaret was a misunderstood and misinterpreted royal. She said that people thought of her as "angry, rude and tough" but "she wasn't tough at all, she was highly vulnerable and often attack is the best form of defense".
( With inputs from IANS )