Patagonia designed its Infant Capilene 1 Silkweight Shirt to add just a tiny bit of warmth to your late-fall and early-spring outings. The polyester and spandex blend makes this set very light and breathable so you can layer under his first winter bunting or his first cold-weather camping clothes. Polygiene's permanent odor control blocks foul-smelling stenches so you can put off doing laundry for another day. The grow-fit feature lets you extend the cuffs an additional inch and a half for your ever-growing youngster.