I feel like the new over reacting mom here. Even though I'm not new to chicks I've never had one be so slow to develop. She is super active and eats well (crop empties fine during the night). She is falling behind the group as they fly around and she can't go with them. The photo's below are a week old. At the time my Easter egger was much larger than the others but the other 3 chicks have since caught up. They all have huge wings, good starts on their tails and feathering out. My welsummer is still covered in downy fluff with tiny wing nubs and that's it. They are now 3 weeks old. Anyone ever had a slow developer like this? Is this a sign of more serious problems? As you can see they started off pretty close.