The nearly 800 graduating seniors of Marjory Stoneman Douglas High School in Parkland, Fla., formed a sea of maroon, wearing white sashes that read “MSD Strong” in a commencement ceremony on Sunday.

The ceremony honored the four seniors who were killed in the Feb. 14 mass shooting at the school, presenting diplomas to the families of Nicholas Dworet, Joaquin Oliver, Meadow Pollack and Carmen Schentrup. Nikolas Cruz, a former student, is charged in connection with the deaths of 17 people that day and the wounding of 17 others.

Pollack’s brother, Hunter, posted several messages about his sister on Twitter on Sunday. “She was ambitious, and was looking forward to moving towards a new path in life that would’ve began today,” he wrote. In another post, he said: “This is a sad day, as I will be walking stage to get her diploma for her.”

April Schentrup, Carmen Schentrup’s mother, did not attend the ceremony, but congratulated the graduating class.

“For me, it is too painful to celebrate w/o Carmen,” she tweeted along with a photo of her daughter. “But I am proud of Carmen’s friends & classmates on their accomplishments. They’ve overcome so much.”

But the somber mood at the graduation ceremony shifted when a familiar, yet unexpected, face took the stage to address the crowd, gathered at the BB&T Center in Sunrise, Fla.

Comedian Jimmy Fallon surprised the graduating seniors as a guest commencement speaker, bringing a moment of levity and laughter.

“You should feel incredibly proud of yourselves,” Fallon told the graduates, adding jokingly, “That doesn’t mean you should rest on your laurels — or your yannys.”

He went on to provide some useful life advice, telling students to stay off carbs but stay on their parents’ wireless plans for as long as possible, the Sun-Sentinel reported.

While his speech was peppered with jokes, the host of “The Tonight Show Starring Jimmy Fallon” also applauded the students for their bravery and courage.

“Every bad experience can have something good come out of it,” he said. “You guys have already proved that. You took something horrific — instead of letting it stop you, you started a movement, not just here in Florida but around the whole world. The whole world has heard your voice and that was you making a choice. And that was you choosing hope over fear.”

Fallon recalled meeting some of the students at the “March for Our Lives,” a national march for gun control organized by Parkland survivors, and called it “an amazing day.” The comedian was just one of many celebrities who attended the March 25 rally that drew hundreds of thousands of demonstrators to D.C. On Monday morning, the students plan to announce the next phase of their movement at a news conference.

During his speech, Fallon added that he and his wife brought their two young daughters because “we wanted them to see what hope and light looks like,” according to the Sun-Sentinel.

As with many commencement addresses, Fallon left the graduates with inspiring words.

“When something feels hard, remember that it gets better,” he said. “Choose to move forward. Don’t let anything stop you.”

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