Skin breaking out with hives
after showering can be dealt with , using luke warm to cold
water for shower please avoid any soap and hot water.
For other issues
The best way to deal with the issues are to have lactose free diet.
1) Fresh, frozen, and canned vegetables
2)Fresh, canned or frozen fruit
3) Bouillon, broth, vegetable soups, clear, soups, consommes, homemade soups made with allowed ingredients
4) rice, spaghetti, white/sweet potatoes
5) soy milk, Nestle's Quik.
6)Plain meat, fish, poultry, eggs, Kosher prepared meat products, soybean meat substitutes, dried peas, beans, lentils, and nuts
If still nothing works and kid still keeps on throwing up you need to visit near by physician and take medical help
Thanks, hope it helps.