After an initial stint at Penn from 2010–12, Killion served as an assistant coach at Sacred Heart for one season before spending three seasons at William & Mary. While with the Tribe, she helped lead the program to back-to-back 15-win campaigns—tied for the fourth-most in school history—and its first-ever postseason appearance with a bid to the 2015 Women’s Basketball Invitational.
As a player, Killion had an illustrious career at Holy Family University. She was a four-year letterwinner and a three-time team captain, a two-time Central Atlantic Collegiate Conference Player of the Year, a two-time ECAC first-team selection, and a two-time second-team selection. She earned her bachelor's degree in elementary education from Holy Family in 2008, and was named to the Holy Family Athletics Hall of Fame Class of 2021 while her 2007-08 team was inducted into the 2017 CACC Hall of Fame.