Very few people know that Buster was actually tested and certified as a therapy dog before Peaches, and six months younger in age. But the reason that Peaches has been working steadily as a therapy dog for the last year and that Buster has not is simply a matter of mode and preference. Buster, despite being far superior to Peaches in obedience and skill performance, has only two modes of operation when it comes to interacting with people: indifferent or smothering.
Here is an example of smothering, with his daddy.