I guessed Opal for bird #2. I guessed Opal because it looked light and grey to me. I don't know opal was sort of a random guess.
You will have to keep us updated with pictures as they get bigger.
Bird #1: Looks like maybe a peach split to white or dark pied.
Bird #2: ______ Blackshoulder split to white or dark pied. Not sure about the color...Maybe opal?
Bird #3: Looks like this one is split to white or dark pied as well perhaps. Blackshoulder too. Color is cameo?
Bird #4: Definitely a...