happy release

   the death of a terminally ill patient

   We use it of others in pain, although they may feel otherwise. Less often as happy dispatch, a translation of the Japanese hara-kiri but without implying suicide. The happy hunting grounds are said to be the post-mortem destination of American Indians, while Dr Johnson professed to believe that, when dead, he might sit in a happier seat:

    ... although when in a celestial frame... he has supposed death to be 'kind Nature's signal for retreat', from this state of being to 'a happier seat', his thoughts upon this awful change were in general full of dismal apprehension. (J. Boswell, 1791 — the Doctor was human after all)