NBC broadcasted Peter Pan live with legendary Broadway star Mary Martin from the mid '50s to the early '60s, giving Allison some big shoes to fill, but she's evidently spent most of her life preparing for the part.
When the casting announcement was made, Allison posted a childhood photo of herself dressed as Peter Pan, writing, "I've been rehearsing for a REALLY long time."
Likewise, Allison's father, NBC Nightly News anchor Brian Williams reported the casting news during a broadcast, saying, "Family members confirm that she's been rehearsing for this role since the age of three and they look forward to seeing her fly."
Following the death of Hook star Robin Williams, Allison shared a video of her flying lessons for Peter Pan. She captioned the Instagram post: "First day of flying lessons for Pan. Thinking about and missing a hero of mine who once did this and left big shoes to fill."
The TV special also stars Minnie Driver as an adult Wendy Darling and Christopher Walken as Hook.