The 27-year-old blonde revealed legendary singer Rod is so thin she could only borrow garments from his wardrobe when she was younger and slimmer.
She told Britain's Daily Express newspaper: "When I was younger I used to wear Dad's trousers.
"The thing is, he was so skinny. I mean, even skinner than he is now, so they only fitted me when I was younger."
Kimberly's younger sister Ruby recently revealed the Scottish rocker keeps all his old stage outfits.
Ruby, 19, said she and Kimberly came across Rod's secret collection in the attic of their family home when they were younger.
Ruby said: "Dad has an attic full of clothes from the 70s and 80s! We used to sneak up there and try stuff on."