During his childhood, Peterson played sandlot ball in his hometown of Chehalis, Washington and was considered a multi-sport athlete, participating in snowboarding, football, and wrestling.

Although he received some college interest in football at the end of his high school days, Peterson chose baseball after large improvements to his talents on the diamond.

Despite helping lead W. F. West High School to two state semifinal appearances, Peterson received little attention from major colleges.

[3][2] He made his first appearance that same night, in a losing cause against the San Diego Padres,[3][4] driving in a run in his pinch-hit at-bat with a groundout.

[5] He started in left field the following day, collecting his first hit,[2] a pinch-hit RBI single on July 24 against Jake Diekman of the Philadelphia Phillies.

[8] Peterson was paralyzed from the chest down in a diving accident on July 3, 2021 and undertook rehabilitation at the Shepherd Center in Atlanta, Georgia.

[8] As a member of the St. Louis Cardinal's 2013 World Series contending team, Peterson attended the 10-year anniversary of the runner-up achievement at Busch Stadium in 2023.