What should I carry for flight journey for my 10 month old baby?

Hello, I think if you are travelling within the country, your flight I assume will not be long. It will be maximum 3 or 4 hours. So, I think basic things, like, baby's water, some little tidbits for her to eat, diapers (of course), some toy, a thin blanket kind of thing, as the temperature inside the plane would be low.