This season is cut short by one episode due to the production shutting down as a result of the COVID-19 pandemic, which makes this the season finale.
According to Bo's video, the following celebrities will appear at Cheyenne's birthday party: DJ Khaled, Billie Eilish, Harry Styles, Taylor Swift, Tiffany Haddish, Drake, J.K. Rowling, Awkwafina, Malia and Sasha Obama, Gritty, Brad Pitt, Danny Duncan, Kylie Jenner, Andre Agassi, Sandra Oh, Criss Angel, Fast & Furious Car, Demi Lovato, Lin-Manuel Miranda, Ryan Seacrest, PewDiePie, Amy Sherman-Palladino, Cole Sprouse, Stuart Little, Hulk Hogan, Kevin Hart, Billy Nye the Science Guy, E.R. Fightmaster, Betty White, Bronny James, Florence Pugh, Amy Klobuchar, Robert Downey Jr.
Brett is playing the Easter Bunny. The name tag he has on says Eggwin.
Amy's fake name tag says "Wunm".
Tony did not appear in Glenn's Kids (2017). Glenn mentioned that the only kids who weren't present for the family photo were the "prison ones," so in all likelihood Tony was in prison, though it's never confirmed on screen.