Wife Nancy Juvonen worked the camera, while 6-year-old daughter Winnie took over for The Roots and the graphic department. 5-year-old Frances, however, was slightly less professional as uninvited cohost.
As Fallon started to speak, Frances literally crashed the scene by shooting down a slide into the room and proceeding to climb all over her father.
"I'm gonna tell some jokes. Want to stand there and laugh at daddy if they're funny?" he then asked his family. "If you hear a joke you think is funny, laugh at it."
They laughed, but it wasn't at what he was saying. Instead Frances kept crawling all over her dad, as Winnie repeatedly stepped in front of the camera lens.
When he asked whether she liked his jokes, Frances flat out told him, "No."
The failed monologue was followed by an interview with Lin-Manuel Miranda, who video conferenced his way into the show from his own home.