J.K.
We keep our air cool so I use the sleepers and gowns and bundle him. I had two babies in May and two in October in Phoenix, I currently just had my 5th in April. I keep them bundled when the air is down but just put them in onesies when it's warm or we go outside. I will keep them in onsies but then I'll cover them with a blanket if the car air conditioning is cool etc. I still get cold in the summer because stores etc. keep their air conditioning very cold. You'll still need those long sleeved stuff at times, I'm sure. Congratulations!