Trust me; I'm a doctor.
(Heroes in Room): Defense +5 / +10 / +15
Heroes with this skill: Kaspar Herab (lvl 1/4/8)
Items with this skill: Dove
Group Therapy's description is a bit confusing. It may seem like it gives heroes the Pack of Dogs and Got Your Back skills concurrently, but what it actually does it allow heroes with either one of those skills to still use their own skill when in the room together even when they normally can't. In other words, a hero with Pack of Dogs can use Pack of Dogs when in a room with a hero without Pack of Dogs, but the first hero wouldn't also gain Got Your Back.