Permanent marker does not come off grout. How do I know? Because I live with an artist. My son draws on everything. Usually I can remove his "art" but last night he decided to take a black permanent marker to the tiles in the hallway. I was actually impressed that he'd drawn circles on the tiles (running over onto the grout), the floor, the stairs, and the back door. He used to only scribble, but now he's making deliberate shapes. Of course, I now have a permanent reminder of that on my grout.
When he was first born, the doctor examined his hands. I'd heard about the line thing, but in my mind, I'd envisioned some kind of colored line or something. Yeah, that doesn't make sense at all and when the doctor explained the common one line crease across the palm, I realized what a dork I was. My son actually has two creases which means that inside the womb he used his hands in a normal fashion. Many kids with DS only have one crease which means their hand movement is somewhat different and usually means they need some form of therapy.
My son can use each of his fingers and can pick up tiny objects. He can also grip a pencil, or, in this case, a permanent marker, and I'm hoping this means he'll be able to write easily when the time comes. I know he can draw easily.
It's fascinating to learn all these intricate details that I took for granted with my other children. Things I'd never considered, but that I've had to watch for and evaluate with my son. It's definitely a learning process and I'm sure I'll learn more from him than he'll ever learn from me.