Delta does not give size dimensions for personal items. Jackets, “small” umbrellas, food, and diaper bags do not count as personal items. Carry-ons must not exceed 22x14x9 inches. Half the size of our popular adult Recon backpack and built to mirror its aesthetics, this 17-liter youth daypack can fit a standard 9.5" x 12" folder and features side mesh water bottle pockets that double as treasure-keepers, and a sternum strap…