Diane Tripleton

Diane is a doctor who used to work with Dr. Roberts at Dream Corp LLC years before the show's current timeline. She and Dr. Roberts were possibly romantically involved, and seem to have a strained relationship these days, as her visit to Dream Corp in the Season 1 episode "Tijuana Zebra" agitates him, and they quickly descend into an argument which upsets T.E.R.R.Y. She apparently was instrumental in the creation of T.E.R.R.Y., who sees her as his mother figure.