We have 2 grown healthy chickens and recently got 3 new chicks (all bantam cochins) first one died 3 or 4 days ago, began behaving weird not moving or eating and just died. We thought it was a flook (she was 3 days). Yesterday our beautiful miss priss (7days) started behaving weird around 8 in the morning, we got her to drink a bit but no eating, around during 8 she seemed to have a heart attack and die. And today deer (8 days old) has been acting the same weird way, not moving she won't eat as my 5 year old lays here holding her asking if maybe she's tired and just needs sleep I'm left wondering what the heck I've done wrong. The three that died we got at 1 and 2 days old. We have one chick left but she is a few days older than the rest and she seems fine. Any insight into this would be great also the main reason for this post is I'm not sure if they are on medicated starter feed. I have heard so many mixed things about either and don't know the difference I guess or the benefits but could this be a reason we r losing our babies?