Singer Toni Tennille has found a new calling after training her pooch to become a therapy dog and becoming a volunteer at an Arizona hospital.

The Captain & Tennille star and her Australian shepherd Smoky cheer up patients once a week at the Yavapai Regional Medical Center in Prescott as part of the Pets Are Warm Support programme.

A source tells the National Enquirer, "Every Thursday that Toni is in town, she and Smoky show up at the centre to visit the patients. Toni is a real sweetheart. She's generous and gives freely of her time. Her dog is super-friendly, and very well-behaved, and whenever they are in the building, they light up the place.

"Sometimes patients are a bit taken back - insisting they know Toni from somewhere... Most patients eventually figure out who she is."

And the Grammy Award winner sometimes even performs during her visits.