The O2 thing doesn't happen on most a/c as there are extra masks throughout the cabin.

An infant at the exit is a def no no in all the airlines I have worked for.

Some wouldn't even allow a newspaper.... IMHO they are right.

... Sorry... that should also read an infant or child shouldn't be by a door near an exit. It depends on the a/c type as to what this means. On some a/c there are about 3 rows that have to be totally clear. On wide bodied a/c it is just the 2 or 3 seats next to the door.

I have been licensed as crew on about 17 a/c types and all differ, not just by type , but also by the peculiarity of the exit, whether it be a cabin crew manned door , or a self help exit.