The storyline of this picture is that Homer and Marge has come out for a caraccident and Marge is badly hurt. It is a small risk that she is gonna stay alive much longer and are pregnant with Bart in the 9 month.
I don`t know if it possible to take out a baby after the mother is dead from the stomach but since this is a cartoonstory everthing is possible
So after Marge dies Homer decides to take out Bart with a cesarian and that`s why he carries Bart on the two last pictures who is in this time
Hope you`ll guys like it