Nobody likes going under the knife, even when they know they'll be anesthetized.

But, that was especially the case for Ruby, a puppy from Colorado who was really stressed out about her upcoming surgery.

Veterinarian Dr. Ross Henderson of the Fox Hollow Animal Hospital had just the prescription for Ruby: he took out his guitar and started singing to her.

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Henderson's office posted a video of Ruby sitting calmly on his lap as he sings an Elvis Presley standard to her.

Ruby looks as if she was never stressed at all, as Henderson sings "I Can't Help Falling in Love With You."

"Sometimes your patient just needs you to go the extra mile to make them feel comfortable," the office said on Facebook.

Darcy Holloway, the hospital manager, said Henderson's second passion is music, and added that the animals always love when he sings to them.

But she still can't tell whether its the man or his music that they like more.

"Whether it is just the one-on-one attention or the soothing melodies, we don't know," Holloway told FOX-13.

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