When using the Instant Pot, the beer does not cook off like it does when boiling or simmering. The liquid is trapped in the steam, so it's really has nowhere to go. There is a bit of evaporation but not enough to say it's completely cooked off. Depending on how much you use, will determine how safe it is for kids to eat. This recipe uses only 1 1/2 cups of beer for the entire recipe which is mostly meant for flavour, so it should be fine for all to consume. Of course, use your judgment.