Biracial beauty hair help.

My daughter is biracial white mom black dad. Her hair had the texture of mom's, but is very curly and gets EXTREMELY oily/greasy everyday. We've tried washing it every day, every other day, every 3 days and 1 time a week and it's always the same. It's like that by the end of the day she's washed it. We also can not get her curls to be under control. Her hair always looks like it's not been brushed it's worse after she brushes it actually it looks like she just got out of bed. If we straighten it it poofs out abs frizzes and Iooks like she been electrocuted. We've tried using product and not. Please give me some suggestions.