'Step Brothers' Will Ferrell and John C. Reilly reunite to serenade Snoop Dogg for his birthday

Uncle Snoop Dogg became one of the "Step Brothers" over the weekend when Will Ferrell and John C. Reilly surprised the Long Beach rapper on stage for his 52nd birthday.

Snoop was a guest at the Greek Theatre on Saturday evening for Ferrell's Best Night of Your Life 2 benefit concert for cancer survivors. After the trio performed, Reilly made an announcement.

"Yesterday was a very special day — it was Mr. Snoop Dogg's birthday — now let's sing 'Happy Birthday' to the greatest rapper in the world," Reilly said according to a video posted on Snoop's Instagram.

The video, taken from backstage, showed the moment when a crew member wheeled out a three-tiered cake set with candles. Before launching into the birthday song, Snoop whipped out a blunt and bent down to use the flame from the candles to light it up.

Read more: Snoop Dogg cancels Hollywood Bowl shows in solidarity with striking actors, writers

"That's what I'm talking about!" exclaimed Reilly.

"Light that s—, son," Ferrell added.

As Ferrell and Reilly led the amphitheater audience through the serenade, Snoop hung his head with a smile, seemingly in disbelief and shock. He then blew out the candles.

"My brothers surprised me," the rapper born Calvin Broadus Jr. captioned the video.

Prior to the birthday serenade, Snoop joined Ferrell and Reilly on stage for a performance of "Boats 'N Hoes," which was featured in the 2008 Adam McKay comedy film "Step Brothers," according to fan footage of the show. Afterward, the trio launched off into Snoop's 1994 hit "Gin and Juice" off his breakthrough album "Doggystyle."

Read more: Will Ferrell is an actor, writer — and frat party DJ? 'Old School' star drops beats for USC students

Other guests at Saturday's benefit concert included comedians Jon Stewart, Hasan Minhaj, Roy Wood Jr., Jo Koy and Patti Harrison along with musical guests Beck, St. Vincent and Jack Black. Proceeds from the concert went to Cancer for College, which offers scholarships to cancer survivors. Ferrell attended USC with the nonprofit's founder, Craig Pollard, who battled cancer during college. The "Anchorman" actor has supported the charity throughout his career.

Earlier this summer, Snoop Dogg had canceled a pair of performances at the Hollywood Bowl out of solidarity with striking Hollywood writers. The Writers' Guild of America reached a deal with studios and streamers in September after more than 140 days. At the time, Snoop's shows would have marked the 30th anniversary of “Doggystyle."

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This story originally appeared in Los Angeles Times.