The totally MM would fit your needs and you can stash things like a sippy cup or bottle on the outside pockets for easy access.
I'm going out on a limb and saying DEELIGHTFUL!!!
I've had lots of tote type bags...neverfulls, saleya, galliera etc...and I think that delightful is the best tote, ever! It's spacious, big, super comfortable, and super cute!