Can my iPhone overheat if I'm on FaceTime for 12 hours straight?

Can my iPhone overheat if I'm on FaceTime for 12 hours straight?

Nope, it'll be fine

I doubt it… But if for any reason it was to over heat your phone will shut off and when you try to turn it on a symbol with a message saying the temperature is too high will appear and it will need to cool down once cool enough you can re use it.

It won't overheat, but your battery is gonna drain like no tomorrow, make sure you charge it while using FaceTime.