Caitlyn Jenner is calling on her Instagram followers to join her in supporting GLAAD's Spirit Day.

The upcoming 6th annual Spirit Day supports efforts to combat the bullying of LGBT teens. Supporters are encouraged to wear purple on Thursday, October 15.

“I just took the @glaad #SpiritDay pledge to stand up against bullying. Join me,” she wrote in captioning a photo of herself holding a sign that read, “I took the pledge. Now it's your turn. #SpiritDay.”

The I Am Cait star smiles subtly as she holds the sign and is wearing a short-sleeved striped t-shirt in the photo.

Past participants in Spirit Day include the White House, the Empire State Building, Oprah Winfrey, Ellen DeGeneres, Cher, Laverne Cox, Kim Kardashian, Demi Lovato, Ariana Grande, Shaquille O'Neal, Good Morning America, The Today Show, The View, The Talk, The Tonight Show, the NBA, the NFL, Major League Baseball, NASCAR, WWE, Facebook, Instagram, Twitter, Tumblr, the Las Vegas Strip, and many more.

Visit GLAAD.org/SpiritDay for additional information.