James,
the Therapy Dog training is basically the CGC (Canine Good Citizenship) training (Basic Obedience) with exposure to people on crutches, in wheelchairs, etc. The two best sanctioning bodies are TDI (Therapy Dogs International) and The Delta Society and they examine the team -- dog and handler -- to certify them for Therapy work.
Our boy, Rowdy, is certified by both TDI and Delta because I wanted to be sure the institutions we work in were comfortable with a 120lb male Rottie. Rowdy and I work in schools doing educational programs with 4th, 5th and 6th graders; in children's hospitals and in convalescent homes. It's pretty intensive work but Rowdy enjoys being with the people and giving lots of love.
For our convalescent home visits, we've worked out a "doggy impersonation" routine which most people really love. It, too, was not a lot of training (you'd love his Rin Tin Tin and Lassie impressions) but it gives us something to do for entertainment value.
Therapy work is one of the most rewarding things I've ever done and I think you and Mahkayla would love it.
Jim