Fergusson, the 10kg cat, is a regular sight in the corridors of Waikato Hospital, cheering up patients and posing for photographs as he goes.
The former show cat is now in a new line of work - pet therapy - through his volunteering at the Hamilton hospital with owner Gill Ballard.
A Maine coon, the largest breed of domestic cat, Fergusson is already heavier than most moggies and, at just 2 years old, he still has two years to grow. A male can typically weigh up to 11.3kg.
Fergusson is so heavy that 67-year-old Mrs Ballard bought him a pushchair yesterday for their weekly visits.
"I tried to get a wheelchair but they're not always available," she said.