The 50-year-old performer crashed his son, Jaden Smith's, set at the music festival in Indio, California, to perform Jaden's 2017 song "Icon."
The crowd understandably went wild, as seen in a video Jaden snapped from stage. Will -- who hilariously recreated Jaden's "Icon" music video last year -- belts out the lyrics to the audience, before staring right into the camera in the clip. Jaden then turns the camera on himself, smiling from ear-to-ear before showing fans cheering with their arms up in the audience.
"Done Did ‘dat! #coachella," Will captioned the video on his Instagram, which Jaden later posted to his own account.
Jaden's sister Willow also returned to the stage on Friday, after opening her brother's set last weekend. She shared a sweet family pic to her Instagram early Saturday morning.
Last week's performance by Jaden was also attended by Smith family friend Jordyn Woods -- who broke her silence on the Tristan Thompson cheating scandal on Jada Pinkett Smith's Red Table Talk earlier this year. See more on her relationship with the famous family in the video below.