If you believe a child is allergic to what your wash clothes in...do you just wash there clothes in plain water to get all the laundry soap out of there clothes

What i would personally do is i would wash them out in water once in a washer then i would wash them again in the washer with a different detergant try using all free and clear its hyperallergenic and works great

Try washing with no detergent and use vinegar as the fabric softener. My husband has extreme allergies and we have used vinegar for years. Leaves clothes soft and no harsh chemicals.

Try to use a different laundry detergent. Either that, or hand wash.

Try to find out if they are allergic to all detergents or just one. I am allergic to SUN laundry detergent and when I use a different one it's fine.