How many oz would you guess your LO gets per day, and how old are they?

My 4.5 year old has been having some constipation issues so we took her to the doctor and one of the first things the doctor asked was how many oz of water does she drink a day. I had NO idea, would probably sounds terrible. She suggested she get 96 oz a day and I tried to not let my jaw drop. I know she doesn't get anywhere near that. I barely do!