Actor and legendary funnyman Will Ferrell helped out his son Magnus Ferrell when the 18-year-old musician played his first live show last weekend during a special charity event. Will came out onstage to play cowbell at the end of one song, invoking his classic "More Cowbell" sketch from Saturday Night Live.

Magnus, one of Will's three sons, performs a style of '80s-indebted dance pop as a solo artist. He released a single called "Back in Place" last month. Hear it below.

Magnus Ferrell, "Back in Place"

The event where the two Ferrells performed was a benefit for Cancer for College, per Consequence. The organization, helmed by Will's friend Craig Pollard, raises money to help cancer survivors attend college.

During Magnus' set, the younger Ferrell played a cover of Radiohead's "Creep" plus original material.

In April 2000, Will starred alongside actor Christopher Walken in SNL's "More Cowbell," which hilariously reimagines the making of Blue Oyster Cult's signature song, "(Don't Fear) The Reaper." The following year, Will joined the band Weezer onstage during their SNL performance of "Island in the Sun."

See the video of Will at his son's gig at Rolling Stone. Scroll through pics of the Ferrells onstage below. Relive Will's SNL cowbell sketch underneath. From Rolling Stone, read some of Magnus' original lyrics here:

Magnus Ferrell's set featured a cover of Radiohead’s classic 'Creep,' along with three originals. That included 'Back in Place,' a thumping piece of dance-pop driven by an irrepressible bass line and slinky guitar lines, with Magnus singing the chorus: 'Now I'm trying to find a way back home / 'Cause I can’t take another day on my own / No I didn't hesitate, now I'm lost, wishing I would've stayed / But now it's too late to put everything back in place.'

Will Ferrell in SNL's "More Cowbell" - 2000

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