I usually bring a teether (since my baby is teething), toys that has lights, and balls that has whole through it. I’m planning going to my nephews bday party so I’m planning to bring a small mat so she can play, nap, or do any belly time. It depends on what your baby would enjoy really. I would bring and leave them in car some extra toys just incase you never know they might want to play with more toys.
We take our babe out for long outings often. The mainstays are: Diapers, wipes, portable changing pad, a full change of clothes for bub in a plastic zip bag (to store poopy clothes if you encounter a blowout), a blanket you can use to cover up their car seat if they fall asleep in it or you can lay it out for play time, a few toys, bottles of you use them for feeding Optional (depending on how your baby naps): front carrier fo wearing them, pack n play for a nap at Grandma's + blackout cover or blanket to drape partially over the crib to make it darker, portable white noise machine You've got this!
maybe bring a pack and play and nap at grandmas?