I was too big for them when they came out, but Underoos come to mind as being cooler and with less crushing/brething issues. Can't recall now if my older son had design undies, but my youngest has some, including Star Wars undies (think Underoos with cartoony graphics).

If it helps the kid get to sleep, it's better than a glass of water or milk, because they'll have to get up in the middle of the night to go pee…LOL

Gordon Long

Then again, there are some people who seem to wear pajamas all day, and they're not hospital patients. When did pajamas morph into casual wear? (And vice versa. Plenty of people no longer wear "proper" pajamas to bed, opting instead for t-shirts, shorts, etc.)