Slow breed or runt?

[butterfliesdoku]

I have a 3-4 week old chick that is growing MUCH slower than it's buddies and am wondering if there is something wrong. This is my second time with chicks. The chick is mixed breed possibly part Wyandotte according to the breeder says.
1st photo taken March 15th, 2nd photo taken April 9th.

 

[LadyCluck77]

Some breeds do mature slower, in my experience. I've never had Wyandottes but my Faverolles certainly grow slower than the other birds, like my leghorns.

Cute chick!