A family of feral cats are not keen on humans but with time, they learn to trust the tenacious human who is also filming them. You can hear in mama cats voice that she does not trust the human, but she learns that the human means no harm and eventually even lets the human handle her babies and even pet her.
The kittens were eventually tamed and adopted according to the video.
Feral cats have a place in the wild. That’s where they are happy. If you come in contact with a feral cat it’s best to Trap Neuter (or spay) and Release. There are many TNR programs across the country, so find one in your area and get those feral kitties spayed and neutered.