I figured I had better check on this before I just assume. Is there hand soap, shampoo/conditoner, etc supplied routinely in the rooms just like at WDW resorts? I knew I would have to bring laundry soap but wasn't sure about the other stuff.
They only refill the toiletries on days your get your room serviced- not every day. Depending on how many people are in your room and how much shampoo/conditioner, etc you all use you may need to bring a small bottle or what they leave may be enough. DD and I have long hair and wash it everyday when we are there so the small bottles they have aren't enough for us.
The hand soap is usually enough. They leave a bar of soap which is plenty. They have a small bottle of dish soap at the sink which is enough.
They sell the Disney shampoos in a larger size in the Mercantile if you run out, and there is also a great new grocery a short drive away that would have lots of hair products. Or you can ask for an extra set for a small price as at other resorts. You can call the desk and they will help you out. Hilton Head is a pretty friendly place.