Krishna revealed this form twice to His mother, Yashoda.
http://wikikrishna.com/index.php?title=GS_1.18:_Vision_of_the_Universal_Form
https://www.youtube.com/results?search_query=Revelation+of+the+Universal+Form
- We read in the Srimad-Bhagavatam’s Tenth Canto (10.7.35–37) that when the child Krishna once yawned happily, His mother saw in His mouth heaven and earth, stars, oceans, continents, and all moving and non moving things.
- A similar incident occurred soon thereafter, when her divine son happened to eat mud (10.8.37–39):
https://www.youtube.com/results?search_query=Revelation+of+the+Universal+Form