You can also manually lock the phone from the lock screen (hit the lock icon at the middle bottom) so that your trusted items don't interfere. You would have to manually unlock it with fingerprint or pattern/password/PIN before moving on.
I haven't been able to unlock the phone the same way your kid did it in the video. At least I feel secure.
I haven't been able to unlock the phone the same way your kid did it in the video. At least I feel secure.