At this point, you know everything about Hollywood’s power couples (and even the ones that time has sadly forgotten), but what about its celebrity sibling power duos? Consider this the yearbook they never had, and consider me the one nominating these pairs for superlatives. Prepare to be amazed — here's something to remember these sibling pairs by and to prove that blood really is thicker than water.

Kendall And Kylie Jenner: The Sportiest Girly Girls

Frankie And Ariana Grande: Siblings Most Likely To Have Each Other's Backs

Mary Kate And Ashley Olsen: Sisters Most Likely To Make The Forbes List

Bella And Gigi Hadid: Most Dynamic Supermodel Duo

Dylan And Cole Sprouse: Brothers Who Define Twinning

Nicole And Sofia Richie: Sisters With The Most Swag

Princes William And Harry: Brothers Most Likely To Marry A Princess

Jessica And Ashlee Simpson: Sisters Most Likely To Make Your 2000s Pop Princesses Playlist

James And Dave Franco: The Brothers Most Likely To Make Funny Look Good

Britney And Jamie Lynn Spears: Sisters Most Likely To Melt Your Heart

Liam And Chris Hemsworth: Best Eye Candy

Beyoncé And Solange Knowles: Sibling Divas Most Likely To Break The Internet

Venus And Serena Williams: Sisters You Least Want To Mess With