Our 8yo daughter occasionally wakes up with nausea of unknown cause in the morning. She likes using a spray or two of the Calm Tummy Bitters to take her mind off of it (she keeps a bottle on her headboard), and she reports feeling better.
We also keep a bottle (of whatever bitter variety happens to be in-stock!) on the kitchen table so the whole family (ages 6 - adult) can use them before meals. This was our first experience with bitters and all of us can use any of the varieties after we got used to the tastes basically after the first dose of each. We don't necessarily notice a difference in digestion when we use them or not, but we enjoy the act of using them when we do remember :)