Will Ferrell and Reese Witherspoon‘s latest film, You’re Cordially Invited, is a family affair on and off screen!
At the New York City premiere of the new romantic comedy film on Tuesday, Jan. 28, the actor, 57, and actress, 48, were joined by the cast and crew, including Ferrell’s eldest son, Magnus. (The Anchorman actor shares Magnus, 20, Mattias, 18, and Axel, 15, with wife Viveca Paulin.)
Magnus tells PEOPLE what it was like to get his song, “Slow Down,” featured in the upcoming movie. He says that while his dad was in the middle of filming, he and his roommate at USC “were kind of in a rut, and wanted to make something weird and out-of-the-box.”
The pair then experimented and made a “really weird-sounding, super-fast, kind of Latin” song, he tells PEOPLE, adding that they shelved it until Magnus decided to send it to his dad.
“Then he was like, ‘Hey,…
