My 1 year 9 month old son has been diagnosed with Celiac disease as well as allergies to soy, egg, fish, milk and peanut just two months ago.It all began with he having eczema/ rashes (all over his body) which won't go away. So, we took him for a blood test which showed that he was allergic to the aforementioned products. Currently, he is on elimination diet with non of these products in his meals. I'm a strict vegetarian and so was my son since birth until he was diagnosed with these allergies. After the diagnosis, he has been on vegan diet as he cannot take dairy products. My question is how could he have been able to consume all these products safely without any allergic reactions until just two months ago (when the rashes/ eczema began)?? I'm worried that if he continues on this vegan diet, he would be lacking in Vitamin B12. He is not able able to drink his S26 Formula milk (due to cow and soy milk in it) or any cow milk at all. We tried giving him Almond milk but his forehead are got swollen. We started with gluten and soy free Rice Milk which seems to be tolerated well by him, though I know it is not nutritionally good enough due to low protein level in it. (I don't have a choice but just to rely on this milk). I tried giving him Health Aid Baby Vitamin (Vegan) drops to make up for the Vitamin B 12 he maybe lacking being on a Vegan diet. This Vitamin drop is free from soy, dairy, egg, gluten and nuts. However, his body didn't seem to tolerate this mixture- he got swollen lips and bumps on his forehead after taking the drops. The ingredient list on this multivitamin formula indicated Sodium Benzoate (preservative, known for exacerbating Eczema and causing Angioedema) which maybe causing the inflammation???? I seriously don't know what has caused the reaction. I gave him tortilla made from Gluten Free Flour (Natural Bio Pty Ltd) which is also free from soy, dairy, egg, and nuts. But I'm suspicious of Lithothamnium Calcareum in it? Can this substance be harmful to a toddler with multiple food allergies??? I'm sacred of introducing any other Multivitamin / B 12 supplement (fearful of additives/ preservatives that may exacerbate my son's skin conditions.) Does anyone know what is the best V B12 supplement for a kid with multiple food allergies?? I don't want him to be on a Vegan diet but to go back to his healthy Vegetarian diet as before. Will love to get him back on his milk / milk products. Will welcome any feedback on the topic.