Molly Davis is the younger sister of Andy. Like her brother, she ages between each of her appearances. She appears as an infant in Toy Story, a toddler in Toy Story 2, a pre-teen at age 12 in Toy Story 3, and a kindergartner during flashbacks in Toy Story 4.
Molly, being a one year old toddler, doesn't have a major part and only appears in a few scenes. Early in the movie while Andy is playing, Mr. Potato Head lands in "jail", which also happens to be her crib. Molly drools all over Mr. Potato Head and takes him apart, much to his later protests. Afterward, Andy takes her downstairs for his birthday party. Because of the aforementioned incident with Molly, Mr. Potato Head also ended up referring to her sarcastically as "Princess Drool." Near the end, she is seen listening to "Hakuna Matata" (from The Lion King) in the car, and giggles when she sees Woody and Buzz in her mirror, trying to reach the moving truck. At the end of the film, she receives a Mrs. Potato Head toy for Christmas, much to the joy of Mr. Potato Head, who wished for her during the first part of the movie.
Molly appears at the beginning, being held by her mother, and at the end where she is seen taking her first steps, with Andy's help. She is mentioned by Bo Peep, who is searching for Woody's hat in her room. She is mentioned again by Woody when he and Jessie are on the plane, because he says, "And he (Andy) has a little sister!"
Molly makes her final appearance in Toy Story 3 at age 12. She is first seen in Andy's room laughing because Andy still has his old toys but is lectured by both Andy and her mom. She then decides to donate many of her things, including Barbie to Sunnyside Daycare, and listens to music while reading a tween magazine. She is then seen at the end saying to Andy, "Aren't you going to say goodbye to Buster?"
Molly makes a brief appearance during the flashback segment at the beginning of the film which occurred before Toy Story 3. She is seen showing her room to her mother and an unnamed guest, whom Bo Peep is given away to. She is then mentioned by Woody after he reunites with Bo and explains to Giggles McDimples that Molly, as a baby, used to cry every night due to her fear of the dark, which broke all the hearts of the toys. However, after Bo was placed in Molly’s room as a nightlight, Molly was able to sleep peacefully. Bo remembers this fondly, but dismisses it because she was a lost toy now and she had a new purpose in life, although the good times she shared with Molly convinced her to help Woody, who needed help rescuing a handmade toy. Molly was not mentioned again after this.
- Although Mrs. Potato Head and Bo Peep are her toys, they seem to be Andy's as we always see him playing with them. Woody mentions in Toy Story 4, that Bo Peep was originally Andy's but was later moved to Molly's room once the Davis family moved to a new home.
- Because of Molly's tendency to drool on any toys, she could get her hands on as a baby (as seen in Toy Story), she earned the nickname "Princess Drool" from the toys, especially Mr. Potato Head.
- In a part of Toy Story 3 when Molly is playing outside the house, it is shown that she might enjoy playing with Buster as well.
- Darla from Finding Nemo makes an appearance in Toy Story 3 on Molly Davis' magazine.
- Someone was holding the model of Molly at the airport in Toy Story 2.
- Many viewers wondered why Andy simply didn't give his toys to Molly before he went to College. The DVD commentary stated that Molly had grown to the age where she was no longer interested in toys, preferring electronics and magazines.
- As a toddler, she often cried a lot at night causing dismay to all the toys in her room, as told by Woody in Toy Story 4 while reminiscing about Bo Peep's early years in the Davis household. To ease her crying, Bo would often turn her lamp on and sleep by her side.
- Technically, Molly was the second human to witness the toys come to life, after Sid (as she briefly witnessed Slinky's attempt at saving Buzz, Woody, and RC via the side-view mirror in the climax to the first film). However, in that case, it was purely accidental, and either way she never would have remembered the events she witnessed as she was only an infant at the time.