When I picked up my order last week, instead of 5 chicks there were only 3. In order to get the one chick that was very important (a SLW which was picked out by my 8 year old) they have said that they can't ship again until the 21st. I assume that I'll have to keep them in separate brooders as they are going to be 3 weeks apart. What do I need to do to integrate them and how do I do it? They're supposed to be all pullets, but after the first snafu I'm not fully confident.