and so.. with just a few days short of hitting the 6 months mark, my son has become incredibly mobile, moving across the room, half crawling, half hopping, half rolling or whatever means possible. put a toy he is interested in from across the room and he’ll scamper across in the ways he knows how. which pretty much means.. NIGHTMARE. today, he rolled himself off the play mat onto the hard marble floor under the coffee table in a matter of seconds and gently knocked his head against the floor. i was aghast. one second he was beside me in the center of the play mat, the next second, he’s…