Border crossing violation

Yoshi has his designated play area (within the blue fabric area on carpet). We didn't want him on the wooden floor as his head tends to lay down so fast and it will hurt a lot. But the more u try to stop him, the more curious he is across the border.... Sometimes when I'm in the kitchen, Yoshi disappears quickly within my sight "where's Yoshi?!".....he rolls and rolls to the other side of the room....very soon, he can crawl too...oh no!!