They grow up so fast!

From the Kardashians and Jenners to the Olsen twins, there are plenty of famous siblings who've grown up right before our eyes!

Miley Cyrus' littler sister Noah has been walking the red carpet alongside her big sis since she was just eight years old. Now, she's 17 and recently released her very first single "Make Me (Cry)." Fortunately for Noah, she's been groomed by her sister to handle the scrutiny that comes with thrusting yourself in the spotlight.

miley cyrus and noah

Miley and Noah Cyrus at the premiere of The Last Song in 2010.

"Miley always says, 'Don't ever look yourself up or read your comments, 'cause you're gonna see stuff that you don't want to see,'" she said. "That's the best advice ever. If it's making me happy, then it's working."

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Miley definitely has her sister's back, and has been raving about her during interviews, too. "She's who I wanna be when I grow up, and that's saying a lot, because she's a lot younger than me," Miley proclaimed.

Click through the gallery to see then-and-now photos of celebrity sisters and brothers who are super close.