The expensive answer is to rent giant industrial Dehumidifiers and High CFM airmovers from a restoration company, but that would get costly quick and really freak your parents out. If the wall is only painted, just keeping air movement on it for a couple of days will prevent mold from starting and dry the wall out. The drywall will act like a natural wick and pull moisture 6 to 8 inches up the wall, but for 15 gallons it shouldn't be that bad. The First place that you will get mold is behind the baseboard and on the carpet under the stand so keep an eye on that area, and focus your fans there. The baseboard prevents the wall from drying out properly. Assuming you posted as soon as this happened, you caught it in time to prevent any real damage.
**IF you think the water ran thru to the drywall on the floor below, you will need to get some airflow going down their as well. We have electric meters to measure the moisture content of drywall that allow us to see if the drywall was affected and to what degree, but They are a touch on the expensive side. I believe some drywall contractors use them as well.
If you have a small basement Dehumidifier get it up to your room and close it in, it will help dry the building materials faster. just watch the water levels in your tank. I didn't catch where you were located, but your home Air-conditioner will lower the general humidity in the house, which will help the walls and carpet dry out as well.