moish,
All my kids are underage, but I do use wine in cooking (it makes for delicious gravy). As SJS noted, nearly all the alcohol burns away during cooking anyway. My daughter can’t eat wheat, barley, rye, or spelt because she has celiac disease (gluten intolerance). It’s not exactly the same as an allergy, but similar. Since most beer, and probably all kosher ones, are made from barley, I wouldn’t use it as an ingredient in a dish I’m cooking for my family.