I got a Nikon Coolpix L830 for my birthday.

Started to read the 204 page instruction manual online. It has a
function called 'pet portrait' where you point & frame the shot and as
soon as it detects a cat or dog it shoots 3 frames without you pressing
the button!

Ever spookier it has 'smart portrait' where you frame a persons face &
nothing happens until they smile. Then and only then it takes a photo!

Tried (the latter) function on my beautiful No 2 daughter. It works when
she smiled showing teeth or not, but no other facial expression would
trigger it.

I'm slightly scared of it!