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Mary-Kate Olsen wore patterned snakeskin pumps to the Los Angeles premiere of ‘The Hangover’ at Grauman’s Chinese Theatre on June 2, 2009 in Hollywood, California. The snakeskin’s color pattern of alternating bands of red, black and white is common to milk snakes. Is herpetology the new retifism?

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Pueblan milk snake (Lampropeltis trangulum campbelli), Denver Zoo.

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Elizabeth Olsen attends the Broadway opening night after party for “Impressionism” at Sardis on March 24, 2009 in New York City. Baring a remarkable resemblance to her older, lime-lit sisters, Lizzie shares the Olsen twins’ preference for bohemian threads.  In fact she and her brother James are name-checked with Elizabeth and James, the fashion line by Mary-Kate and Ashley. Last night we are pretty sure Lizzie was wearing the long, sheer camel colored dress that Mary-Kate belted in 2007 for the presentation of Calvin Klein’s new collection at P3, Marylebone Road in London, England.  Who do you think did the dress justice?

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Mary-Kate Olsen attended a screening of The Wackness in New York City ready for battle last night. It was noted by New York Magazine that she appeared jovial at the event, flashing her pearly whites. There was something familiar about her ensemble, a white, silk kimono-esque floor-length gown, cinched with a thick black leather belt. It called to mind the neo-martial arts costume worn by 70’s era Luke Skywalker.

Upon further reflection we realized that Mary-Kate has been given to flights of fancy in the Star Wars vein on more than one occasion. From a full gold encasement at the MET Costume Institute Gala, a la 3CP0 to an organically neutral gown worn to a Calvin Klein show last year Mary-Kate has been either channelling “The Force” or translating late 1970’s fashion milieu along the lines of George Lucas’ vision.

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Actress Mary Kate Olsen arrives at the Metropolitan Museum of Art Costume Institute Gala, Superheroes: Fashion and Fantasy, held at the Metropolitan Museum of art on May 5th, 2008 in New York City. Mary Kate dons gold sequins, looking reminiscent of Shirley Eaton’s gold body paint in the James Bond film ‘Goldfinger’. With the success of Mary Kate and Ashley Olsen’s recently launched fashion lines, one could say everything this mini-mogul touches turns to gold.

Hilary Duff seems to have taken her inspiration not from a Superhero, but rather from the city that has provided a backdrop and home to so many. Duff’s beaded silver dress with Art Deco detailing conjures images of one of Gotham’s most famous buildings, the Chrysler Building.

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Hilton…Simpson…Olsen…Spears…Duff…Kardashian…. Famous sisters are the best (and the worst). Celebrity siblings are all over the place right now, but we have always been interested in famous women who come in pairs. The Gabor sisters, The Landers sisters, Joan and Jackie Collins were duos previous generations kept tabs on.

Sisters are fun to watch: When sisters begin to share the spotlight sometimes they try to differentiate themselves from one another by establishing defining looks, such as Mary Kate and Ashley Olsen (dark boho vs sunny blond) or Jessica and Ashlee Simpson (sunny blond vs edgy rocker). We can witness them ease into their roles and equalize aesthetically (Olsens/ Simpsons).

Sisters are sexy: When sisters’ looks and attitudes diverge wildly, the game of:“which sister would you rather____?”is likely to ensue. When their looks converge, the pairing still provides fuel for fantasies.

Sisters are us: When one sister falters we can shift our hopes to the other one. When one seems appears to be the underdog, we can root for her.

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Though it is fascinating to watch sisters who are both in the public eye, it is refreshing to see a celebrity with her “normal” sister. Antonia Kidman is primarily a journalist, but glided into the public eye by accompanying Nicole to parties, premieres and shopping. Mia Farrow is the most widely known daughter of Maureen Sullivan, yet she has siblings with fantastic bone structure who remained somewhat unknown despite brushes with acting.  One of Mia’s sisters was the inspiration for the Beatles’ Dear Prudence.  Whatever a lesser known sister is up to, they offer a different perspective on her famous sibling. The citizen sister grounds her celebrity sister more than many interviews or magazine pieces can.

View this lightbox to see the full gamut of our favorite sisters.

Pictured: Peaches and Trixie Gelof vs. Catherine Deneuve and Françoise Dorléac, Lindsay Lohan and Ali Lohan vs. Maria Scicolone and Sophia Loren, Lisa Roberts Gilliam and Julia Roberts vs. Cameron Diaz and Chimene Diaz

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Fashion’s two favorite pixies, Ashley Olsen and Mary Kate Olsen, made a spirited appearance at the Chanel fall 2008 ready-to-wear fashion show in Paris. The fashion-loving twin sisters wore matching oval-shaped sunglasses to the show. Sunglasses inside: chic or shady? Discuss!

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Working a post-bobo chic look in New York City, Mary-Kate Olsen had some trouble yesterday managing her cell phone, squatting down to take the call, then dropping her purse—all while simultaneously smoking a cigarette. (Don’t do it MK; think of your beautiful skin!) Hopefully your lunch at Bubby’s was less stressful.

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