It is normal and expected that a devotee receives boon from deities like Siva, Vishnu etc., But, I came across an incident in Mahabharata, in which Garuda grants boon to Vishnu.
"And the son of Vinata then met Vishnu on his way along the sky. And Narayana was gratified at that act of self-denial on the part of Garuda. And that deity, knowing no deterioration, said unto the ranger of the skies, 'O, I am inclined to grant thee a boon.' The ranger of the skies thereupon said, 'I shall stay above thee.' And he again spake unto Narayana these words, 'I shall be immortal and free from disease without (drinking) Amrita.' Vishnu said unto the son of Vinata, 'Be it so.' Garuda, receiving those two boons, told Vishnu, 'I also shall grant thee a boon; therefore, let the possessor of the six attributes ask of me.' Vishnu then asked the mighty Garuda to become his carrier. And he made the bird sit on the flagstaff of his car, saying, 'Even thus thou shalt stay above me.' And the ranger of the skies, of great speed, saying unto Narayana, 'Be it so,' swiftly wended on his way, mocking the wind with his fleetness.
I also heard that Sanatkumara grants a boon to Shiva and takes birth as kumara Swamy. Which scripture mentions that?
And are there any such other incidents in scriptures?
