What is it about a pair of sexy sisters? The sight of that much good DNA within the same branch of a family tree just warms the heart. Of course, in the movies, actresses playing sisters usually aren't related, but if they're hot, you're all too happy to believe they are for 90 minutes.

Honestly, could Scarlett Johansson and Natalie Portman really be sisters, as they are in The Other Boleyn Girl? No way, but having that sort of superior A-list hotness under the same roof is an entertaining thought. 

The latest couple of movie siblings joining the list of fictional fantasy duos (or trios or quartets) are Lizzy Caplan and Alison Brie, who are in Save the Date, opening this weekend. Where do they rank in the pantheon of hot on-screen sisters? Well, you're about to find out.

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