Your daughter seem to be having some viral illness which lead to the hair fall
Hair fall is quite common following any kind of illness. Even certain medicines can cause hair fall as a side effect.
But you need not worry about it.
It is a completely reversible process.
As soon as she recovers from the illness or stops the medicine, hair regrowth will start.
However, since hair will grow at their own speed, so might take more than a month to notice the hair growth again.
Hope it helps
Dr Geetika Paul