Elle Fanning knows that having a sister means you also have an expanded wardrobe, but only if you can sneak an item of clothing away.

The 21-year-old actress recently admitted she stole a bright pink bikini from her older sister Dakota, 25, and brought it with her on her vacation to Italy.

“The pictures you take and the pose you make when you know you stole your sister’s bathing suit and got away with it! MWAHAHAHAHAAHAHAH,” the "We Bought a Zoo" actress wrote on Instagram on Monday.

Meanwhile, the elder Fanning had a little trick up her sleeve.

She casually replied in the comments of her sister's post, “It’s fine. I have 3 with me and they are all yours.”

ELLE FANNING FAINTED AT A CANNES FILM FESTIVAL DINNER BECAUSE HER DRESS WAS ‘TOO TIGHT’

Even though the sisters tease each other, it's all love deep down.

“My sister, Elle, and I are really close,” Dakota told Shape magazine. “We always have been. We’re very different, but we’re very connected. We don’t talk every day, but we don’t have to. We just have that special bond.”

“There’s no one I want to succeed more in this business than my sister, and I know she wants the same for me,” she said.