Caitlyn Jenner's grandchildren call her "boom boom".

Caitlyn Jenner

Caitlyn Jenner

The 67-year-old reality star has 11 grandchildren in total, including her most recent granddaughter Dream Kardashian, her stepson Rob Kardashian and Blac Chyna's six-month-old baby girl.

And Caitlyn has revealed her decision to undergo a gender transition in 2015, from Bruce to Caitlyn, has caused confusion amongst her younger grandchildren, so she is now referred to by the funny nickname.

Speaking on UK TV show 'This Morning' on Friday (12.05.2017), she said: "I just had my eleventh grandchild. As a matter of fact they are (beautiful) I did do a good job.

"Kendall is a top model in the world and its amazing to me. They've all worked very hard. Of course, when you've had 10 children the kind of cool part about having grandchildren is that they only know Caitlyn, that's kind of fun. "

When asked by hosts Ruth and Eamonn what his grandchildren call her, she said: "Pro-nouns are always very interesting. I've got a couple of them call me boom boom. The little ones do, that's always good."

Caitlyn said her daughters Kendall and Kylie were also confused as to what to call her after the change, however, she simply wanted to be called "my dad, she".

She explained: "My daughters, Kendall and Kylie, my youngest ones, at first they was like oh my god what do we call you now? And I said ... dad.

"I will be your father until the day you die. And so I have no problem with that. They still call me dad and that's fine with me.

"It's kind of tough as 'dad-she' but they're really good at it, especially Kendall, you know 'my dad, she."

And the former 'I Am Cait' star admitted she is finally at peace with her life as a woman.

Asked if she feels content now, she said: "Oh, so peaceful. And that's the nice part about going through this, I've done everything i needed to do to get to this point in my life and be open about it. I'm very blessed. I'm blessed with a great family that is understanding now. Some done a better job at dealing with this than others, which you know has to be expected, I have 10 children, but I think what they say is, 'I'm a better person today' because of all of this. Sometimes it takes them a lot of time to realise that, they think it's going to be so different, and it's really not, I'm still in so many ways the same person and I still love them to death and eventually those who are still on the outside will come a bit closer."