I am new to the chicken world. After losing 3 babies within 48 hours, we were left with 5 babies. They are now 3 weeks old, but we suffered another blow. A black snake got my 2 smallest( Easter egger and buff orphingtons) yesterday. After putting some bullet holes in that bast###, and putting mothballs out, we want to add to our 3 remaining chicks. Any suggestions on the best way to add the news ones? Should we get chicks that are 3 weeks, or newly hatched? Our chicks are still in brooder, so a little concerned on the best way to do this.