Originally, Amber was cold, spoiled, bratty and envious. When Sofia became a princess, Amber took an immediate disliking to her, fearing that Sofia would beat her at her own game, with her brother James remarking that Amber "won't be the fairest of them all." She was mean to Sofia and hated being called out for it. Amber's jealousy increased when the other children acted friendly to Sofia. Amber acted manipulative and even tricked James into humiliating Sofia.
Later, after she ripped her ball gown, became too upset to attend Sofia's ball and found out that Sofia made a mistake with a spell to become a better dancer that put everyone in the ballroom into an enchanted sleep, Amber apologized to Sofia and told her that she was happy to be getting a stepsister. Here, Amber corrected Sofia by stating "Sofia, we're sisters!" After making up, Amber and Sofia worked together to undo the spell, showing that for all of her faults, Amber is not entirely a brat and now truly considers Sofia as her sister and knowing when to admit her mistakes.
Amber loves her family, especially her father King Roland and her twin brother Prince James. This is especially noticeable in "Two Princesses and a Baby" where, after she asks Cedric to change his birthday but accidentally turns him into a baby, she shows motherly affection and regretted her decision to change him. Her relationship with her new stepmother Miranda got off to a rocky start, but now she admires her with great affection, even giving her a rose flowered unicorn bush to show how much she cared for her.
Even though she tends to manipulate and ignore James, she appears to actually love and care about her brother, judging by her reaction when James says that he likes Sofia better than her, which was the first time that she was shown feeling truly depressed.
As the series has progressed, she is becoming more responsible, kind and respective towards Sofia by teaching her more about being a princess. She tries keep Sofia out of harm's way as well. And while she is still holding on to her old haughty, vain and spoiled behavior, Amber is steadily improving not only as a princess, but as a person as well.
Though she mostly has a cold manner, she can become emotional and even a bit violent at times. She even hit Wormwood with a broom to maneuver him into his birdcage to allow Sofia to get the book with the counter spell for the sleeping spell. Amber has also furiously chased a wild carpet and often scolds others' errors in displeasing her--this includes squirting glue and glitter on her dress (in the case of Princess Leena) or (in the case of her peacock, Praline) failing to let her succeed.
Amber can be a bit bossy, believing that bigger is better and that simple is not good enough. She tends to take over party-planning, believing that she knows best. She has to be reminded that people have their own ways of throwing parties. Her desire to win can also get her into trouble, such as when she cheated to win the school's costume contest. Occasionally, her selfishness, such as wanting her own birthday, causes trouble for others as well. Through the consequences of these actions, they have taught her valuable life lessons.
Amber is a fair-skinned 9 year old girl, having blonde hair and amber eyes that gave her her name. She almost always wears a chartreuse gown and a crystal tiara inset with emeralds, often with a floral deep red fan in her hand. She often wears costumes covered in feathers, except for her butterfly "costume".
Her hair reaches past her shoulders but it is often held in place by a tiara, making it appear a little shorter. The full length of her hair is seen during the sleepover in "The Big Sleepover". It also tangles easily.
When Sofia comes to live in the castle, Amber and James are told to welcome her in and Amber lies to the king, saying that she will. At first, Amber seems to try and help Sofia while acting rude to her at the same time, but grows jealous when King Roland announces that Sofia will have her own ball, even though Amber and James had one when they were born. Later on, when Sofia is given the Amulet of Avalor, Amber happens to pass by and see this, growing envious of her and becoming even more jealous of her when the other children at school start paying more attention to Sofia than to her. She tricks James into making Sofia sit on a magic swing that flings her into the fountain. Everyone thinks James did this on purpose and Amber takes none of the blame. When they arrive back at the castle, James tells Amber that what she did was wrong, but she ignores him. At school, Sofia continues to get more attention than Amber, who spies on her. When James offers to bring Sofia to dance lessons, Amber gets an idea--she gives Sofia Cedric's magic shoes, which start to cause Sofia to crash while dancing and the other children to laugh at her. During the incident, Sofia realizes that Amber tricked her and refuses to talk to her, though Amber pretends to feel sorry for her. James, who knew of the plan, finally decides to confront his sister about it. When he comes to talk to his sister, Amber has put on a blue gown for the ball. When James calls her out on her prank, she counters him by reminding him that he played a prank on her as well, even though the previous prank was really Amber's fault as well. Amber is hurt when James says that he likes Sofia better than her and leaves. When Amber rips her gown and tries to call James back, she overhears the maids saying that Sofia is the prettiest princess, causing a now-dejected Amber to run crying to her room. After Sofia accidentally puts everyone at the ball to sleep with a spell, she goes to see if Amber can help after getting encouraged to do so by Cinderella. Amber, still depressed, tries to ignore Sofia, but she sees what Sofia did and blames herself. She and Sofia try to undo the spell, but are attacked by Cedric's raven Wormwood. Wormwood attacks Sofia and Amber attacks him with a broom and knocks him into a bird cage. He accidentally reveals where the spell to wake everyone up is and they take it and read it, undoing the spell. Before doing this, Amber teaches Sofia to dance. Amber tells James that she helped her, much to his surprise. All of them end up dancing with each other.
Amber is a major character in the series. While Amber is caring and close to Sofia, she remains a little vain and prissy in certain regards to what she thinks being a princess is all about, like when she discouraged Sofia from trying out for the Flying Derby Team, disliking how Sofia had invited Jade and Ruby to their princess slumber party as the two were village girls, etc. However, she became more lenient towards Jade and Ruby, even joining them when they offered good ideas for decorating the Enchancian Flylight Coach. In both instances, however, Amber learns her lesson and gradually becomes a better person. Amber was also afraid to try riding a magic carpet since it was new to her. But trying it, she got to explore the kingdom of Tangu and meet Princess Jasmine. She learned a lesson about trying new things and thanks Sofia for it.
- In her debut, Amber is the classic jealous stepsister (and still can be on occasion,) but she reforms after getting a taste of her own medicine and seeing what her actions indirectly caused, similar to Anastasia Tremaine.
- Four of Amber's gowns have been damaged in some way, the first being her ball gown which was ripped, the second was her nightgown which was stained with chocolate, and her signature dress got covered in glue and glitter. In "Two Princesses and a Baby", her signature dress is damaged two times, the first time was when baby James wiped his hands with chocolate on them and the second was when Amber and baby James played water fight.
- Jasmine, Mulan and Rapunzel are currently the only Disney Princesses that Amber has met.