Thank you for your query.
I presume that your daughter does not have a nose bleed at present. In case there is a bleeding then an opinion from an ENT specialist
You rightly pointed out that the congestion could be due to the ragweed season. In case it persists then appropriate medication will have to be given after consulting the doctor.
I shall not worry about the prominent vein unless some obvious complaints are there. However it can be shown to the treating doctor to rule out any underlying problem.
I hope I have answered your query to your satisfaction.