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Playboy founder Hugh Hefner is having "lots of fun" with his rumoured new girlfriends, 19-year-old twins Karissa and Kristina Shannon.
The magazine mogul's ex-girlfriend Holly Madison has revealed Hugh is spending most of his time with the 19-year-old blonde beauties.
Holly said: "They're a lot of fun. I would never try to personally pick Hef's new girlfriend. I would like him to take his time and actually get to know somebody - which he never does! But as long as he's having fun, I'm happy for him!
"He's having lots of fun with them - and a lot of other people!"
Although Holly, 28, is pleased 82-year-old Hugh is moving on since their split, she has warned Karissa and Kristina about the pressures of living in the Playboy mansion.
Holly, who hasn't yet moved out of the famous residence, added to Usmagazine.com: "They are a little young and definitely like to have a good time. I just hope that they can take this new fame with a level head."
Meanwhile, Kendra Wilkinson - who is soon set to split from Hugh - insists the Playboy founder will struggle to find a new set of girlfriends to match her and Holly.
Kendra, 23, said: "Hef will always be Hef. You can never change him. He'll keep loving women, keep loving the big boobs and blondes.
"But it's very rare to get a good batch like Holly, Bridget and I. I don't think they'll be any better than us."
Bridget Marquardt, 35, is still romancing Hugh.
- BANG! SHOWBIZ
