The idea of a nature spirit guide for Pocahontas was first developed with a male character in mind, named "Old Man River". When actor Gregory Peck was brought in to play the character, he declined and suggested that Pocahontas's spirit guide be a maternal figure instead. The character was reimagined as a tree of life figure whose foliage would mark a seasonal change in the story. Veteran Disney story artist Joe Grant would develop the character further as a grandmother figure for Pocahontas, inspired by an early story sketch of an old tree stump telling the story of Pocahontas 300 years later. Jeffrey Katzenberg initially objected to the character, but added humor in the form of various tree puns ended up winning him over.
Grandmother Willow is a sentient weeping willow tree that serves as an adviser to Pocahontas. She is depicted as being an ancient and wise figure. She can be comical at times, as in her words, there is still snap in her old vines. She serves mostly as a spiritual adviser and it is implied that she served a similar role to Pocahontas's now-deceased mother some years before. Being a willow tree, many other animals make their home in her branches.
Grandmother Willow first appears after she is consulted by Pocahontas. Pocahontas relates to Grandmother Willow her doubts about Chief Powhatan's plan to have her marry Kocoum, a brave yet serious warrior. Pocahontas then relates a dream she has been having, involving a spinning arrow. Grandmother Willow advises Pocahontas that the spinning arrow is pointing Pocahontas down her path. When Pocahontas asks what her path is, Grandmother Willow advises Pocahontas to listen and allow the spirits of the earth to guide her. Pocahontas then hears the wind and, after climbing up Grandmother Willow's branches, sees "strange clouds" (which happen to be the sails of the Susan Constant, a ship belonging to the English settlers).
Later on, Pocahontas leads John Smith to Grandmother Willow. Smith is rather frightened at first but quickly warms up to Grandmother Willow after she compliments him, saying that he has a good soul and is handsome. While talking, Ben and Lon, two of Smith's fellow settlers, come looking for him. Grandmother Willow has Pocahontas and Smith hide. She then scares Ben and Lon off, first by intentionally tripping them by lifting her roots, then by whipping them with her vines. The two run off, but John Smith decides to leave before more come looking for him. He and Pocahontas agree to meet at Grandmother Willow that night. After he leaves, Pocahontas worries whether or not she is doing the right thing by meeting him again. Grandmother Willow wants to see him again and reminds Pocahontas of her dream. Pocahontas realizes that her spinning arrow may have been pointing to him.
That night, Grandmother Willow listens as Pocahontas and John relate to each other that their respective communities are planning to go to war. Pocahontas asks John to come to speak to her father, but John refuses. However, Grandmother Willow persuades him otherwise by using the analogy of ripples. Ripples start small but quickly grow, but someone must start them. She then notes that Pocahontas and John can only be together once the fighting stops. John agrees, but before he can go to Powhatan, Kocoum who was sent by Nakoma attacks him. John's friend Thomas, who had been watching, comes to John's aid and kills Kocoum. John takes the blame and is imprisoned by the Indians and sentenced to die at dawn.
That night, Pocahontas tells Grandmother Willow of John's fate. She encourages Pocahontas to try and stop them. Pocahontas believes that she has followed the wrong path and feels lost. Meeko brings John's compass to Pocahontas, which has a spinning arrow. Grandmother Willow identifies it as the arrow from Pocahontas' dream. As sunrise comes, the arrow suddenly stops. Grandmother Willow encourages Pocahontas to go and let the spirits of the earth guide her.
Grandmother Willow doesn't appear for the rest of the film but is referenced near the end when Pocahontas brings the injured John medicine made from Grandmother Willow's bark, which is supposed to help with his pains.
In the second movie, Grandmother Willow plays a more minor role. Pocahontas visits Grandmother Willow and tells her of her own concerns about crossing the ocean and attempting to stop the potential war between her people and the settlers. Grandmother Willow tells Pocahontas to "listen to the spirit within," but when Pocahontas tries it, it doesn't work due to the forest animals making too much noise. Later, when Pocahontas is in London, Pocahontas sees the trees and sings that Grandmother Willow would just love them. At the end of the film, when John Smith and John Rolfe are arguing over what Pocahontas should do to save her people from Ratcliffe's armada, Pocahontas goes into the woods alone and takes Grandmother Willow's advice.
She listens to the spirit within again and decides to return home.
Grandmother Willow appeared briefly in two episodes of this series. First, she appears in "Jiminy Cricket", when Jiminy Cricket mentions that the audience should "respect [their] elders". Her second appearance occurs in "Chip 'n' Dale".
Grandmother Willow appears at Disney's Animal Kingdom in the Song of the Rainforest binaural sound show at Rafiki's Planet Watch and in the former Pocahontas and her Forest Friends show at Camp Minnie-Mickey. She also makes a small cameo in the Florida version of Fantasmic! and has a segment in the Disney Dream cruise show Believe, where she sings "Listen with Your Heart" to a practical father so that he can believe in magic.
- Willow trees usually only live for approximately seventy years but at most one hundred years. However, in the film, Grandmother Willow is four hundred years old. She ages more like an Oak Tree than a Willow.