Tammy's appearance is a mix of Timmy and Tootie's looks, she has her father's hair color and nose, but her mother's eyes. She wears glasses with a thick cat's eye shaped frame similar to her mother's (sometimes she wears contacts instead), and has long hair with a pink hairband, similar to her mother-in-law, Trixie Tang. Tammy wears a white shirt, a pink plaid skirt and blue shoes. Both she and Tommy inherited heat vision and spider powers that their father once had.
Tammy is an extremely nice girl and not selfish like her brother and father. Much like Tommy, she really loves her family and parents, especially her mother, Tootie. Tammy is considered by many kids to be a cute girl, and is Jessica Prestonovich's best friend, alongside Celia James and Mitzie Mulligan. She also likes Remy Buxaplenty's son, Otto, as she has a crush on him.