We have had our chicks now for a little over a week. When we got them, some were 1 week old and some were 3 days old. We got 15 rir and 3 bantam frizzles. So, now they are 2 weeks 2 days and that rest are 1 week 5 days old. We have them all in a rabbit pen together (half wooden box, half cage). The older ones are VERY active in there but most of the little ones can hold their own. However, yesterday morning, my husband found one of the young ones dead in there. He found another one dead this morning. There is a 3rd one that is not looking so good. It just sleeps right under the heat. I tried moving it to food and water this morning, but the older ones were just running all over it so it went back to under the heat lamp. What could be causing these younger ones to not do so well? The rest other than this one look really healthy and active, even the other younger ones and the bantams. Should we separate this one out? Should we be concerned about disease or is this fairly common with chicks? I have read that when raising baby chicks, it is not uncommon to lose a few. It is just sad and disheartening and then you worry if something is wrong with it that will spread to the others. We have a large hen house ready for them, so it may be that we move them into it sooner that we thought, so that these older ones can play and not run all over the smaller ones, and just not let them out in the run yet. Thanks for any advice!