James Madison (2025): Redshirted during the 2025 season to retain a year of eligibility...Enrolled at James Madison University in January 2025 and participated in spring practice with the program.

Personal: Callen is majoring in Sport Management and Operations at Idaho State and attended Carrollton High School in Georgia after moving from Idaho for his senior season. A versatile athlete, he earned Georgia 6A Honorable Mention All-Region and All-Conference recognition as a senior and was previously Idaho's top-ranked recruit in the 2025 class before relocating. Callen was a two-time Idaho 5A All-State selection, first team as a junior and second team as a sophomore, and a two-time first team All-Southeast Idaho Conference honoree. He helped Carrollton reach the 2024 GHSA 6A state title game and was part of Highland High School's 2024 Idaho 5A state championship team, as well as the 2021 state runner-up squad. Callen chose Idaho State for the community and coaching staff, enjoys spending quality time with family and friends, listens to "I'm Back" by Raq Baby before games, supports the Las Vegas Raiders, and can be found on Instagram (@kai.callen). He comes from a strong football lineage, with his father Atari Callen having played defensive back at Cal and Idaho State and his stepfather Rudy Griffin having played defensive line at Alabama and now serving as a defensive line coach at UT Martin.