Ah, the simple satisfaction of stumbling onto a parent hack. From Molly:
I just turned our Pack ‘n Play on its side, threw a large thin blanket over it and voila — instant fort. I can’t believe I didn’t think of this sooner. My babes are crawling in and out of it screeching and screaming with pleasure. Ahh, five minutes of peace. Maybe someone has already written you about this [Nope. — Ed.], but I’m feeling like a super genius right now!
As you should, Molly.
Related: Games you can play with a flat sheet