Let's just hope the smaller one died of starvation from being immature. Failure to thrive chicks almost always die in the first few weeks.
If this other chick is eating well, the full crop would be normal. But check it in the morning before it eats. Its crop should be flat then. If not, give it coconut oil for possible blockages. Maybe give it coconut oil right now.
Hydrogen peroxide may clean wounds, but the purpose of gentian violet is to turn the wound from red to purple so it doesn't look like blood. It also will disinfect the wound. You can get it from a pharmacy.
Are any of the other chicks starting to behave sick?
If this other chick is eating well, the full crop would be normal. But check it in the morning before it eats. Its crop should be flat then. If not, give it coconut oil for possible blockages. Maybe give it coconut oil right now.
Hydrogen peroxide may clean wounds, but the purpose of gentian violet is to turn the wound from red to purple so it doesn't look like blood. It also will disinfect the wound. You can get it from a pharmacy.
Are any of the other chicks starting to behave sick?