One chick much bigger than others... why?

[Jaylee52]

Hi forum - I hope you all can help!

I have four chicks that I got all on the same day. They should have all been day-old chicks, especially because I went to the feed store the same day they received their new delivery of chicks. 3 of the 4 started out the same size, with 1 of the 4 (the gray easter egger) being a bit on the small side. But now they are 3 weeks old today and the easter egger has caught up, but the Welsummer has taken off and grown HUGE relative to the others. Does this mean she's actually a roo? or not a Welsummer? Or hogging all the food? I don't see her bullying the others when I check on the brooder.

I included a picture of them now at 3 weeks old and some solo pics of them at about 4 days old.

(In the picture of them at 3 weeks, the Welsummer is the big one in the back center. The Easter Egger is the gray one at front left, our Wyandotte is front right, and the Salmon Faverolle is behind the Wynadotte bending over with her head down).

(In the solo pics, the welsummer is the brown stripey one.)

 

[debid]

I can't see the chest feathers. Welsummer males get black chests and will show some sign of that even if the first feathers while the females will have a rosy, light chestnut.

 

[debid]

Oh, and yes, chicks can grow at different rates even when there isn't a problem or a large size difference expected at maturity. These are all females and the same age. The one sticking her neck out was a massive chick but an average sized adult.