Parker is the second recruit to commit to Penn State over the last four days.
Harrar is Penn State men's basketball's first to earn the award since 1995, while Parker is women's volleyball's first representative since 2018.
Nittany Lions old and new have received new jersey numbers ahead of the 2022 season.
After earning her first national team call-up, Coffey will join former Nittany Lion goalkeeper Alyssa Naeher on the squad.
Miller's announcement comes three months after stating his recruitment was "107% shutdown."
The Penn State wrestling legend knocked out his opponent, John Noland, in 33 seconds.