I think you might also look into the true allergy verse intolerance issue. My ds2 with gut issues (now we know it was Celiac Disease) was having reactions to my breast milk, horrible (green frothy diarhea which burned his skin, screamed all the time and no medical doctor could help him, LLL leader said it was hind milk foremilk issues, nope). I went dairy free thinking that would help and it did, but not 100%, he was surviving at the time. I knew it wasn't an allergy just b/c IGE reactions are on a totally different level.
I wish I had known then what I know now!
Many individuals crave the foods that they are intolerant to. Especially wheat, as it has an opiate effect in some individuals -- Dangerous Grains goes into this.
Dairy in general is not widely tolerated by adults, especially pasturized. My ds2 can not tolerate pasterized dairy, but is fine on raw dairy after we healed his gut.
My dairy free experience was a good one after 15 months nursing and 14 1/2 of those being dairy free -- I've never really gone back. I'll have an occassional yogurt, but I'm not the milk drinker I used to be and I'm healthier for it IMO. If I do have ice cream that I have not make from raw dairy, I get sick, I just try to remember that when I crave that Dairy Queen Blizzard!!!
My son was 100% dairy free as well until he was 2 yr old at which point I was so frustrated with doctors I gave up trying to figure out what was wrong with him. I just kept taking foods away that made him sick. Fortunately, one insightful pedi caught the symptoms...
So, if a naturopath tells you that you are allergic to milk (take it as an intolerance and they are probably right) and go dairy free for your kid! And follow JaneS advice on healing the gut! I used probiotics on my ds2 as an infant, I think everything I did is why he was not sicker and did manage to grow enough to be considered healthy for a time.