Here's a couple of videos featuring baby owls.

The first one is by youtuber A S Goprod from a gopro camera set up outside a nesting burrow. The owls know the camera is there, and one of the babies does what all babies do; tries to eat it. We also get hissing, stretching and baby owl butt.

The second video is by Roger Smith from the Small Breeds Farm Park & Owl Centre in Herefordshire, which is apparently kind of a zoo specializing in small animals and owls. They hand rear the babies apparently.