My daughter is 7. she came home with a sore on her chine that look like a scratch it spread big and has move to her arm and foot now.. just looks like a scab but it keeps getting bigger what could this be?

Doctor can examine: Could be a skin infection, so her doctor or the ER should evaluate. Impetigo is a skin infection, usually from strep bacteria. Treatment can include a topical antibiotic ointment, but usually it is treated with an antibiotic by mouth. It helps to keep the wounds clean, such as with one daily bath. If oozing, keeping a dressing on them helps (should be a breathable, not occlusive dressing).