Kendall Jenner appears to have lightened her usually dark brunette hair -- what do you think of the look? Credit: courtesy of Kendall Jenner

Recently blonde Kim Kardashian isn't the only one in the family who's lightening up! The reality star's younger half-sister Kendall Jenner also appears to be trying out a new hair color. On Sunday, Sept. 22, the 17-year-old model showed off some honey-colored locks in a selfie posted to Instagram.

Jenner's hair, like Kardashian's, is usually a dark brunette. But in the picture she shared online, it looks much lighter. Unfortunately, the caption she posted alongside the photo offers no clues about her new 'do; it's simply a sleepy-looking emoji.

This is not the first time the Keeping Up With the Kardashians star has kept fans guessing about her hair. In February 2012, she tweeted a snapshot of herself as a blonde, with the caption, "New look…? What do u think?" However, she later revealed that the 'do was a wig. "Don't worry! Still a brunette! Fooled you," she wrote.

In any case, Jenner has had a busy few days. She and older half-sisters Khloe and Kourtney Kardashian, along with younger sister Kylie Jenner, attended the iHeart Radio Music Festival in Las Vegas, Nev., where they posed alongside a scantily clad Miley Cyrus.

An insider revealed to Us Weekly that Kendall and Kourtney and Kylie and Khloe -- in the midst of a devastating marital crisis with Lamar Odom -- held hands as they walked over to the stage to watch the provocative singer's set. Afterward, all four walked over to her trailer for the quick photo op.