I think it's just a British way of writing. The Brits say all kinds of awful things like that as a form of humor but they're still very loving parents.
BTW, just wait 'til James is three, you'll be thrilled to have thirty minutes of peace while he naps! ;-)
I know ... we're doing 3 for the 6th time. But when James is 3, his younger brother will be Perfect :-).