Standard wisdom is that giant quail chicks grow 100% a day for the first couple of days. Sounded nuts, but it is close to right.
Here is a picture of the chicks a couple of days ago:
The small chick is not a runt, he was born about 24 hours later than the others, that is the only difference.
Now look at a similar picture:
They gave all grown a lot, but he still looks like a runt. In another 2 weeks; he will begin to catch up. In a month, you will not be able to point him out anymore....
BTW, They eat a Lot! :D I like their song, pleasant to hear. I won't mind having them outside, LOL!