Sometimes a handshake and autograph just won't do.
But making one of Greenberg's many difficult days a little better was one of her favorite singers, Bette Midler, who had previously met Greenberg.
This get-together was a bit different, however.
Greenberg got a chance to chat with the Divine Miss M. on the phone.
"You're such an angel," Midler tells Greenberg in a conversation that becomes more emotional as it goes on. "Such a wonderful soul."
When Midler asks Greenberg if she can do anything for her, Greenberg tearfully requests, "Could you fulfill one of my dreams?"
It was hearing Midler sing "Wind Beneath My Wings" to her.
Bette Midler attends The Bette Midler NYRP 18th Annual Spring Picnic at Gracie Mansion on May 30, 2013 in New York City. (Credit: Getty Images)
Midler's vocals, tired and somewhat scratchy from an earlier performance, are nevertheless full of emotion, her voice breaking toward the end of the iconic ballad.
Greenberg died shortly after the phone call.
Here's the footage (the singing starts at about 4:40):