|Hometown:||Santa Ynez, CA|
|High School:||Santa Ynez|
Guillemin earned three top-18 finishes during the 2018 Western State Conference Championships. She finished 10th in the 1,650-yard freestyle final with a time of 22:07, shaving 38 seconds off her previous best time. Guillemin also finished 18th in the 200 free ad 15th in the 500 free final with a season-best time of 6:13.25, nearly 19 seconds better than her seed time. Guillemin was an all-league and All-CIF water polo player for Santa Ynez High School. Her senior year, the Pirates won the program’s first CIF championship. An honor roll student, she earned two coach’s awards. She is a biology major.