Khloe Kardashian and her sisters, Kourtney and Kim, still call Caitlyn Jenner 'Bruce'. 31-year-old Kardashian revealed  their continued use of Jenner's pre-transition name in an interview on Australian television earlier this week.

Khloe KardashianKhloe Kardashian at an event at 1OAK in Las Vegas in March 2015.

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Speaking to The Project, promoting the new Kardashian Kids clothing line, Kardashian explained how, although the family had come to terms with Jenner's transition, there's just one thing they haven't been able to change as yet but Jenner has permitted them to continue using 'Bruce'. 

"We don't like to say that Bruce is gone, per se. We, my sisters and I, we will call Caitlyn 'Bruce,' and we've been told that's completely fine," the Keeping Up With the Kardashians star said (via Us Weekly).

65-year-old Jenner revealed her true gender identity to the world in April by appearing on the cover of Vanity Fair. Jenner revealed she had chosen the name Caitlyn and the name of her upcoming series, I am Cait, is certainly making a statement about how she wants the rest of the world to see her and the name she wishes to be called. 

However, for her family things are slightly different. They've had to adjust and relatively quickly to Jenner's transition and Khloe has revealed how she, when hearing Jenner's voice, still doesn't picture her as Caitlyn.

"She has told us we are allowed to call her any name we want to," Kardashian continued. "Because on the phone, when she calls me, it's the same voice as Bruce. And if I'm not physically with her, it's hard to remember in the moment that I'm talking to Caitlyn, if that makes sense."

On the subject of Jenner's voice, in a preview clip of I Am Cait, Jenner revealed she was struggling to develop a more feminine voice and it was a part of her transition which was proving particularly difficult.

"Women cannot relate to the whole voice thing," Jenner says in the clip. "They don't see it as being that important when it is that important, not only for you to speak and order and do all that kind of stuff, but very important for your soul that you're feeling good about that."

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