My kids and friend and her baby are all allergic to soy. Soy lecithin does not cause reactions. It's so processed, I don't even know why it's considered food. So, I doubt it's the lecithin you need to worry about it. They all can handle soybean oil pretty easily, too. Of course, every person is different.
I'm thinking your child may be allergic to soy (what other forms have you eaten?) and may be allergic to something else, too. Reactions do sometimes take a while to show up.
I have no links, sorry. It's possible she has been reacting all along, you just didn't know the signs. After all, blood in the stool is a pretty far-along reaction.
I would look up allergy info and see if you eat a lot of any other common allergens, if I were you.
I'm thinking your child may be allergic to soy (what other forms have you eaten?) and may be allergic to something else, too. Reactions do sometimes take a while to show up.
I have no links, sorry. It's possible she has been reacting all along, you just didn't know the signs. After all, blood in the stool is a pretty far-along reaction.
I would look up allergy info and see if you eat a lot of any other common allergens, if I were you.