Here's the intro to the episode #3 of The Judy Garland Show when Liza Minnelli was the guest star. That's a beautiful performance with Judy singing Gershwin's song "Liza" while surrounded by pictures of her daughter.
Liza Minnelli performed a medley for her mother on their concert at the London Palladium in 1964. This performance was from the second night, and that's why it's not included in the DVD
