Bender claims that he didn't know robot sex could lead to reproduction. In Futurama: The Beast with a Billion Backs (2008) (V), The Robot Devil traded an army of the damned in exchange for Bender's firstborn, which he traded.
Why would the professor cut open Bender's son's head to get the card slot when earlier on he showed there was a door on the back of the kid's head to get easily to the slot.