She has short blonde hair with a tail in the back, a heart-shaped face with brown eyes, dark lashes, and a dimple in the right corner of her mouth. She is also small for her age. She wears a clay pendant, painted red with an "H" scratched on it that Matt made for her in art class and gave it to her for Christmas.
Haley has a 7-year-old brother named Matt Braddock who is profoundly deaf. She is fluent in American Sign Language and uses it to communicate with Matt & often translates for him when they are with people who don't understand sign language as well. Haley can be very protective of Matt, but she sometimes feels resentful of the attention that he gets.
She and Matt participated in the BSC pet show and they win the "Best Pet Handlers" prize. Haley dressed as a gypsy fortune teller named Madame Leveaux as a part of the Stoneybrook Elementary School fundraiser for the Zuni reservation; she wins a telescope for the most creative fundraising idea. She dresses up as Madame Leveaux again for Vanessa's haunted house.
Haley attended the Valentine's Day Masquerade and entered the "funny-face race" at the BSC Mini-Olympics.
In Claudia and the Little Liar, Haley gives the BSC members a hard time when it comes to homework, but it is later revealed that Haley is struggling in school.
She leads a group of kids to put together a project to explain why the BSC are the best baby-sitters.
- Being competitive
- She can be competitive with Vanessa. They were temporarily ex-best friends after wearing the same swimsuit to Stoneybrook Day Camp, but they later reconcile.
- Haley dressed up as one of the Three Stooges with Vanessa and Charlotte to cheerlead for the Krushers' World Series game.
- Went to the Valentine's Day Masquerade party in Stacey's Ex-Best Friend.