Scarlett Johanssonis hoping to keep her past a secret from her kids.

During an appearance onThe Drew Barrymore ShowWednesday, the 37-year-old actress answered questions forDrew Barrymore’s “The Final 5” segment. TheSingstar — who is mom to 7-year-old daughterRose Dorothyand 7-month-old sonCosmo— revealed the one thing she hopes her children never know about her.

“My daughter may have asked me this before,” Johansson admitted. “I used to smoke when I was younger and I’m so ashamed. I just don’t want her to ever think that I ever thought it was cool ‘cause she can never, ever, ever smoke.”

" ‘Cause that’s what you do. You forbid your kids from doing things and then they don’t do them," she quipped. “So yeah, I just hope she never figures that out.”

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Scarlett Johansson attends the premiere of Illumination’s “Sing 2”

TheBlack Widowstar might have some trouble keeping her previous smoking habits a secret from her little girl because she recently toldInStylethat Rose is currently at an age where she is curious about everything.

“Why are you tweezing your eyebrows? Why are you curling your lashes? What’s a tampon? What’s it for?” said Johansson, imitating her daughter.

“She asked me why my underwear went up my butt crack, and I had to try to explain what a panty line was,” she recalled. “I was like, ‘‘cause you don’t want a line in your pants,’ and she was like ‘Why?’ And I was like, ‘‘cause then you could see my underwear,’ and she was like ‘But youarewearing underwear.’ Like I know, it’s weird.”

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Johansson also revealed that Rose is finding her mom “a little” embarrassing nowadays.

“I do a little dance when the school bus pulls up, and she doesn’t like that,” Johansson confessed to Fallon at the time. “Of course, then I exaggerate it even further.”

source: people.com