We're getting super curious about three of our chicks. We got 20 assorted rare breed chicks from Meyer three weeks ago. We also have one from our original order of 77 from four weeks ago that we can't figure out. First (3 weeks old): Second, three weeks old (black with white head in the middle): Third, four weeks old, but smaller than the three week old chicks. The buff next to it is the same age: Thanks ahead of time!