- "Sit up straight, hold up your microphone. Now sing!"
This cheerful young girl is a wonderful singer, coming up with song lyrics off the top of her head. Annie's pride and joy is a portable microphone, which she always carries with her. She loves animals almost as much as she enjoys singing while in music. She's the only person, besides Leo, to have ever piloted Rocket.
Annie is a young girl around 4 years of age, the smallest of the group. She has blonde hair styled into pigtails with pink hairbows. She wears a blue overall dress (pink in Season 2) and a green undershirt (pastel blue in Season 2). She wears a pair of pinkish-red Converse-like shoes (blue and white shoes in Season 2). Her dress is usually accompanied by a front sole pocket and seams down the side.
As the youngest of the quartet, Annie is the singer behind the group. Annie is defined as always adventurous. She is also described that she might be the youngest but she is the bravest. Annie resides with her brother Leo, a redheaded child the leader of the team. Both Annie and Leo do everything beside each other. Annie has an affection for balloons, singing, and horses. She, like the rest of the team, seems to have arachnophobia. In “Our Huge Adventure”, Annie and the team faced their arachnophobia to save a bundle of butterflies and then easily fled the scene.
Annie loves her friends and will do anything for them. During the events of "Annie's Solo Mission", Leo, Quincy, and June were blowing large bubbles and got caught inside one. Using Leo's flying lessons, Annie flew Rocket around the world by herself to get them.
Annie also seems to be small-minded at points, pointing out the obvious in situations. She also dislikes being smaller than normal as seen in "The Incredible Shrinking Adventure". She didn't know the definition of "mission" in "How We Became the Little Einsteins: The True Story", but learned it thanks to her friend June.
In season 1 at some points, Annie's singing was not the best (even though she is the singer of the group) but it matured through the progress of season 2. Annie was originally going to have a country-inspired motif during the early stages of the series, wearing cowboy boots and having freckles. She looks different from her sibling Leo, who has tan skin and green eyes. Sometime during animation, Leo and Annie both had major redesigns making them closer to having a family relationship.
Annie seems fond of her friends and appreciates their company. Annie also may have thalassophobia as seen in "Quincy and the Magic Instruments", as she constantly shouts when talking to Quincy waving her hands at the same time. Annie also is a very bubbly-like girl, constantly giggling at points. Leo, Quincy, June, and Rocket all congratulate and cheer for Annie when she sings. Annie is good at improvising; she can make up and sing songs right off the spot, often when the team is off to save or help a creature or even when the team is feeling down.
During season 1 Annie sang with the singing posture of placing her hand on her chest and with one hand in the air. In season 2, she was granted access to a microphone to help her sing louder. Annie hates when her microphone is missing.
Throughout the series, Annie overtook new hobbies and interests such as her obsession with horses. She has befriended other singing animals, usually animals or creatures that are down. Annie uses her voice to cheer up the creature and get them in a go-get-em mood.
Annie is also very intelligent for her age, knowing big words that a normal toddler would never know. This is seen roughly through season 2 as during season 1, Annie struggled with her words, asking June for assistance. Annie can speak to animals through song, and can tell if the animal is down or happy by the tone of the animal's vocals. Usually, if the tone is high it means the animal is happy or scared; if it is low it means the animal is mad or sad. When Annie identifies the tone, she will make sure to help the animal feel better. She can also do this with Rocket, identifying tones of Rocket's singing.
She is fully optimistic, finding everything in her surroundings nice. She gets amazed by the slightest of things. This can be seen in "The Treasure Behind the Little Red Door" when she faced her fear from "Our Huge Adventure" (spiders) to befriend a smiling spider.
She made an appearance at Walt Disney World as a puppet in Disney Junior - Live on Stage! in Disney's Hollywood Studios Theme Park and Animation Courtyard. She also made meet-and-greets with guests, just like the other Little Einsteins, except for Rocket.
- She is named after jazz singer Annie Rossi.
- She was the only character who has piloted Rocket by herself.
- She loves animals, but she is afraid of spiders, just like the rest of the team (as seen in Our
BigHuge Adventure), except for the one in "The Treasure Behind the Little Red Door" and the one in "Rocket the Bug". It is also shown in Our BigHuge Adventure that she is afraid of bats.
- She loves dolphins as proven in Pirates Treasure, but her favorite animal of all is a horse as seen in "The Great Schubert's Guessing Game".
- She owns a metal-colored microphone with orange music notes that she won in a song contest.
- When she wishes to urgently point something out to the team, her usual catchphrase is "Look, look, look!"
- She might have arachnophobia (fear of spiders).
- In Season 2, the color of her shirt changes from green to light blue, and the color of her jean dress changes from blue to pink.
- When she is really happy, her smile gets bigger.
- It has been revealed that she might have a crush on Quincy.
- In the episode "The Birthday Balloons", after she thanks Quincy for his balloon, he gives her a wink and she lets out a small giggle.
- In "The Christmas Wish", Annie complimented Quincy's idea to use his wish box to wish for drums to drum the wooden soldiers as very brave in a very sweet tone.
- In "The Northern Night Light", just as Quincy's fear of the dark starts to get the better of him, Annie comes over to him, pats him on the shoulder and asks if he's okay.
- Quincy always seems to find Annie's singing enjoyable.
- Annie loves to hear Quincy play his instruments. One example shows how happy she is to see Quincy play his French horn in "Whale Tale".
- Most of the time, the two sit/stand next to each other.
- In Rocket's Firebird Rescue, Annie was given Music Power, and may now have it permanently.
- She loves animals just as much as she loves singing.
- She always sings her special goodnight song to herself at bedtime, as mentioned in A Galactic Goodnight.
- Though she is the only singer in the group, she can be found singing along with June.