Based on the pictures and the description, this looks like an irritant or allergic dermatitis. The redness, itching and mild swelling suggest ongoing inflammation. Since it has been there for a week, it’s important to calm the area and prevent further irritation
Next Steps
If the redness increases, if there is pain, warmth, fever, spreading rash, or if the swelling becomes more prominent, she should be examined in person to rule out infection or other causes. A dermatologist visit is recommended if symptoms don’t improve in 3–5 days