I just wanted to give a shout out to Karen Prell, who did some animating work for TF2 and various other valve games back in the day.
https://www.karenprell.com/Karen_Prell_Home.html
I had the pleasure of working alongside Karen this winter on the set of Fraggle Rock: Back to the Rock. She was incredibly down to earth, and answered my many questions regarding the meet the team videos and working at valve.
Check out Fraggle Rock on Apple TV, Karen has been playing Red since the 80s!