I see what you are both saying, but I think I'm leaning towards cutting out all dairy because that's the best way to check that dairy is the problem and then add yoghurt to see if that makes a difference or see if it's a level of tolerance thing and it builds up but she can tolerate a little bit IYKWIM.
Ice cream is my favourite thing in the world too. That was really HARD for me to give up when I was dairy free while feeding them both. But I had a great recipe that just used coconut milk and berry jelly (as in jello). Problem is that I don't like giving DD berry flavoured jelly because of the colouring etc. I wonder if I could make my own using frozen berries and gelatine??
E has milk on her cereal - I know that is easy enough to swap out and I think I'd go for oat milk. She does like drinking milk too, but I think I could convince her not too or replace it with other milk. She has yoghurt frequently for lunch, loves ice cream, we have cheese in lasagne and other dishes etc. Ugh some things will be ok, but others ugh so so hard. And especially when going to parties etc. And we go to the ILs for dinner with the whole family (at least 23 of us - it's mad!) once a week and that's a dairy-fest. It was so hard for me when I was dairy free let alone for her to do. Plus I find since I eat low gluten, it just means we eat more dairy. It will be really hard to cook low gluten plus dairy free without doing separate meals I fear.
Anne, remind me of what happens to Amelia when she has chocolate? Hives is it? I have always wondered about E and chocolate after eating chocolate cake at birthday parties. We had chocolate cake for her birthday (plus J's birthday is just 3 days before and he had a chocolate cake too so we were eating cake for days) then the next week was Easter where she had chocolate every day for like a week. After all that it was very clear that E + chocolate = bad! It was just like chocolate in= chocolate out. Just

Ok ladies, we need someone with BTDT experience to come along and convince us to make the jump -that it's worth it!