Sheena is a PSD(Psychiatric Service Dog) and is being retired this year(2013). Daya is a PSD in training.
A PSD is a type of service dog trained to assist their partner who has a mental illness. Here is my favorite link
that describe what a PSD is, does and how they are trained.
International Association of Assistance Dog Partners
This next link is to a page I created that is about Canadian Service Dogs and the regulations for each Province.
Canadian Service Dog Information