My daughter is experiencing eye swelling, purple rash around eyes, headache, sinus pain, fever (better by: with fluids, rest) (worsened by: dehydr...

Get checked: Most of your question got truncated but it sounds like she should see a doctor and get examined to make sure it isn't a serious infection.

Infection: This sounds like an infection of the soft tissues around the eye, either peri-orbital or orbital cellulitis. It often arises from a sinus infection. It can develop into a dangerous infection so getting it checked with a proper examination is a good idea.