The first, hazy weeks of caring for a newborn are much like that old children’s rhyme (one we’re sure you’ll come to know). You can’t go under it, you can’t go over it, you have to go through it. But ...

Queen Rihanna once said that she only gets three or four hours sleep a night, while Sydney Sweeney claims that she can cope on just two. Meanwhile, Madonna once told Rolling Stone that she struggles ...