Can you simply substitute soya/rice/almond "milk" and other products for dairy? Soya milk eventually starts tasting like food (after you've lost the will to live, or maybe that's just me), and rice milk seems very digestible - personally, I find it too sweet. My godson has severe problems with dairy, and has been on rice milk since he was weaned (his mother is not vegetarian, but also has dairy allergies and simply has no dairy at all in her diet). A doctor I used to babysit for, back in the mists of time, had his children on goat milk due to their dairy allergies. He said children are very rarely allergic to goat milk (beware, it tastes exactly like strained goat).