Kid's Footed Sleeper (Sleepwear)

One piece, feet included, closed by a zipper that usually runs the full length of the body. Nothing separates at the waist, so no gap opens across a back and no sock goes missing. Size runs start at preemie and newborn and usually stop around 5T, which is about when children want to dress themselves.

The zipper is the design. A two-way zip, one that opens from the ankle end as well as the top, lets you change a diaper without pulling a sleeping baby's arms out of the sleeves. A fabric guard at the top keeps the metal pull off the chin. Newborn sizes add fold-over cuffs that cover the hands, since babies scratch their own faces before they can control their arms. Walking sizes add rubber dots on the soles, because a knit foot on a wood floor slides like a sock. Cotton knit versions are cut snug to meet the sleepwear rule, while fleece and polyester versions are loose and flame resistant instead.

A sleep sack does a different job entirely. It replaces the blanket, has no legs, and goes over a sleeper rather than instead of one. Two-piece pajamas start where the sleeper ends, at toilet training, and give up the covered feet in exchange. A baby gown leaves the feet bare and the bottom hem open so a night change takes seconds, which beats even a two-way zip. But it is meant for babies who are not yet rolling.

Babies who kick every blanket off and bedrooms that sit cold are where a sleeper works best, because feet stay covered and no waistband presses on a full stomach. Toilet training ends it: a child who has to be unzipped from the shoulders will not make it in time. A warm room ends it too, since a sleeper plus a sleep sack in a 75F bedroom is one layer too many.

Feet run out before anything else, so measure there first by pressing the toe end and feeling for a finger's width of space. Run the zipper fully open and closed a few times before buying, since a cheap zip catches exactly when your hands are full. Turn sleepers inside out to wash so the sole grip does not rub away against the drum, and watch the toe seams, because that is where the first hole appears.