Yeah. Ok. I'm a sap. Even muppets can make me emotional.
Sid Ceaser proposed to Sara Prindiville as a Muppet. He's been a Muppet fan all his life. So, when the time came, Sid ordered custom-designed Muppets that resembled the two of them, and produced a film using those muppets. It was shown along with the previews at a theater Sid took Sara to. She recognized who the Muppets were as soon as she saw them, and, well... said yes! This is that video.