Barbara, Mary and their guest Dave Letterman celebrate a big BGS milestone. #pie #happybirthday #letterman Subscribe to Letterman: https://bit.ly/3GeOIAg Follow Letterman on Social: Facebook: https://www.facebook.com/DavidLetterman Instagram: https://www.instagram.com/letterman/ Twitter: https://twitter.com/Letterman TikTok: https://www.tiktok.com/@letterman Welcome to the Letterman YouTube Channel, home to all your favorite clips from Late Night and Late Show - as well as conversations with the writers, producers and performers who helped make it all happen. And for those of you who like Miscellaneous, you may very well find some Miscellaneous here.