Mouch was the latest Firehouse 51 team member missing from an episode. Why wasn't he in Chicago Fire season 13, episode 12?

Chicago P.D. Season 12, Episode 12 featured Delaney Williams and Benjamin Levy Aguilar on the cast in a very dramatic installment.

One Chicago's latest crossover put Chicago P.D.'s Sergeant Trudy in the crosshairs and gave the franchise's best character a ...