The "Kenan & Kel" cast is honoring the life of the late rapper Coolio.

"Aw, Here It Goes," the series' theme song, was written by him.

The series was based on two characters from the Nickelodeon comedy sketch show "All That."

On the show, Kenan Thompson and Kel Mitchel played two high school students who got into trouble.

The series aired from July 15, 1996, to July 15, 2000.

On September 28, 2016, Coolio passed away at the age of 59.

Kenan shared a "Wait, now Coolio!!!" message on his Instagram Story.

Kel posted a lengthy, moving tribute on Instagram.

He remembered several "great memories" he had with the well-known rapper.