We have a large baby - 11lbs at 1month, about 23 tall - and these, fortunately, run slightly big, so by the age of 2months we are still fitting great in those pajamas, while we have to size up in all other brands.additionally, I purchased a similar gerber set of boy pajamas and their fit is smaller, so we definitely outgrew them by now.  Overall, I highly recommend everyone to stock up on those, out of all the types of babys yclothing those are the simpliest and fastest to put on and off, without unnecessary buttons, very soft and good quality, and given how fast babies are growing - the price is definitely hard to beat.