Recs for what to bring on road trip

CrazyMary77

In a couple weeks DH and I will be taking a long road trip with LO from South Florida to NY for a couple days, then to MA for a couple weeks to visit family. I know that we'll need to take it slow and stop at least every couple of hours. I'm making a list of all the things we'll need to bring. Although I know that we can always stop along the way to buy anything we might forget, I'd like to be as prepared as possible. Aside from the obvious necessities, those of you experienced in taking an infant on road trips, what things would you recommend bringing that you may have not initially realized would be necessary or helpful? LO will be 3-months-old and I EFF.

On a side note, I am concerned about LO spending so much time in the car seat. She tends to get overheated in it, and spending all that time in the same position may make for a cranky baby. Hopefully frequent stops where we take her out of the seat will take care of that.