"We had the hair fairies over," Sienna Miller quips to PEOPLE about how she dealt with her 4-year-old daughter contracting lice from school

By Jen Juneau
December 15, 2016 12:30 PM
Andy Kropa/Invision/AP

It may seem like celebrity parents and kids don’t have to deal with the same challenges of everyday life that many do, but in Sienna Miller‘s case, that’s just not true.

Case in point? Her 4-year-old daughter Marlowe came home from school recently with something most parents dread having to deal with.

“She got nits for the first time — like head lice,” the actress, 34, told PEOPLE Tuesday at an N.Y.C. screening of her new gangster drama Live By Nightwhich premieres in theaters on Christmas Day.

Adds Miller, “She’s like a petri dish of germs. She just brings home things from school. It’s the joy of having a child in school.”

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“She said, ‘I’ve got ants in my head,’ ” recalls Miller. “And I was like, ‘Oh no!’ I knew exactly what it was.”

The single mom — she and Marlowe’s dad Tom Sturridge split in July 2015 — says that despite the slight panic in hearing her daughter brought lice home, she nipped it in the bud quickly.

“Yeah, we dealt with it. We had the hair fairies over,” she says.

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Now that the lice issue is behind them, the mother-daughter duo is focusing on enjoying the holiday season together in a low-key, relaxing way.

“We’re gonna be in England. We’re gonna be snuggled up with old movies and fireplaces, and Mama’s gonna have some wine,” shares the actress, who attended the premiere alongside costars Elle Fanning, Chris Messina and Ben Affleck — the latter of whom also directed and produced the film.

“Gonna stuff our faces with turkey and food, like we do every year, and try not to squabble as a family,” she adds.

  • With reporting by BLAKE BAKKILA