Dressing an August baby

This may be such a dumb question but my first was a December baby.

I’m due 8/24. I live in Philadelphia so we’re usually in the 80-90s then. By the end of September, I’d say we start cooling off.

I bought long sleeve cotton sleepers because of air conditioning. Should I be putting a short sleeve bodysuit on under it? I hate not doing that because I feel like the buttons and or zippers will be irritating.

Any other summer baby suggestions are welcome!