Joslyn has been acting in her school's shows since she was eleven, getting as involved as she could. Beginning in ensemble roles in shows like Honk! and Beauty and the Beast, she eventually took to the stage with some of her favorite roles like Marian in The Music Man, Rosie Alvarez in Bye Bye Birdie, Marmee in Little Women, and Charlotte in Charlotte's Web. She also participated in the Governor's School for the Arts as a musical theatre student in 2021.